diff --git a/lib/src/generator/generator_frontend.dart b/lib/src/generator/generator_frontend.dart
index 37143b2b7f..802cf1ef1a 100644
--- a/lib/src/generator/generator_frontend.dart
+++ b/lib/src/generator/generator_frontend.dart
@@ -72,66 +72,66 @@ class GeneratorFrontEnd implements Generator {
     var indexAccumulator = <Indexable>[];
     var multiplePackages = packageGraph.localPackages.length > 1;
 
-    void generateConstants(Container container) {
+    void generateConstants(Container container, Library library) {
       for (var constant in container.constantFields.whereDocumented) {
         if (!constant.isCanonical) continue;
         indexAccumulator.add(constant);
         _generatorBackend.generateProperty(
-            packageGraph, container.library, container, constant);
+            packageGraph, library, container, constant);
       }
     }
 
-    void generateConstructors(Constructable constructable) {
+    void generateConstructors(Constructable constructable, Library library) {
       for (var constructor in constructable.constructors.whereDocumented) {
         if (!constructor.isCanonical) continue;
         indexAccumulator.add(constructor);
         _generatorBackend.generateConstructor(
-            packageGraph, constructable.library, constructable, constructor);
+            packageGraph, library, constructable, constructor);
       }
     }
 
-    void generateInstanceMethods(Container container) {
+    void generateInstanceMethods(Container container, Library library) {
       for (var method in container.instanceMethods.whereDocumented) {
         if (!method.isCanonical) continue;
         indexAccumulator.add(method);
         _generatorBackend.generateMethod(
-            packageGraph, container.library, container, method);
+            packageGraph, library, container, method);
       }
     }
 
-    void generateInstanceOperators(Container container) {
+    void generateInstanceOperators(Container container, Library library) {
       for (var operator in container.instanceOperators.whereDocumented) {
         if (!operator.isCanonical) continue;
         indexAccumulator.add(operator);
         _generatorBackend.generateMethod(
-            packageGraph, container.library, container, operator);
+            packageGraph, library, container, operator);
       }
     }
 
-    void generateInstanceProperties(Container container) {
+    void generateInstanceProperties(Container container, Library library) {
       for (var property in container.instanceFields.whereDocumented) {
         if (!property.isCanonical) continue;
         indexAccumulator.add(property);
         _generatorBackend.generateProperty(
-            packageGraph, container.library, container, property);
+            packageGraph, library, container, property);
       }
     }
 
-    void generateStaticMethods(Container container) {
+    void generateStaticMethods(Container container, Library library) {
       for (var method in container.staticMethods.whereDocumented) {
         if (!method.isCanonical) continue;
         indexAccumulator.add(method);
         _generatorBackend.generateMethod(
-            packageGraph, container.library, container, method);
+            packageGraph, library, container, method);
       }
     }
 
-    void generateStaticProperties(Container container) {
+    void generateStaticProperties(Container container, Library library) {
       for (var property in container.variableStaticFields.whereDocumented) {
         if (!property.isCanonical) continue;
         indexAccumulator.add(property);
         _generatorBackend.generateProperty(
-            packageGraph, container.library, container, property);
+            packageGraph, library, container, property);
       }
     }
 
@@ -157,88 +157,93 @@ class GeneratorFrontEnd implements Generator {
         indexAccumulator.add(lib);
         _generatorBackend.generateLibrary(packageGraph, lib);
 
-        for (var class_ in lib.classesAndExceptions.whereDocumented) {
+        for (var class_ in lib.classesAndExceptions.whereDocumentedIn(lib)) {
           indexAccumulator.add(class_);
           _generatorBackend.generateClass(packageGraph, lib, class_);
 
-          generateConstants(class_);
-          generateConstructors(class_);
-          generateInstanceMethods(class_);
-          generateInstanceOperators(class_);
-          generateInstanceProperties(class_);
-          generateStaticMethods(class_);
-          generateStaticProperties(class_);
+          var canonicalLibrary = class_.canonicalLibraryOrThrow;
+          generateConstants(class_, canonicalLibrary);
+          generateConstructors(class_, canonicalLibrary);
+          generateInstanceMethods(class_, canonicalLibrary);
+          generateInstanceOperators(class_, canonicalLibrary);
+          generateInstanceProperties(class_, canonicalLibrary);
+          generateStaticMethods(class_, canonicalLibrary);
+          generateStaticProperties(class_, canonicalLibrary);
         }
 
-        for (var extension in lib.extensions.whereDocumented) {
+        for (var extension in lib.extensions.whereDocumentedIn(lib)) {
           indexAccumulator.add(extension);
           _generatorBackend.generateExtension(packageGraph, lib, extension);
 
-          generateConstants(extension);
-          generateInstanceMethods(extension);
-          generateInstanceOperators(extension);
-          generateInstanceProperties(extension);
-          generateStaticMethods(extension);
-          generateStaticProperties(extension);
+          var canonicalLibrary = extension.canonicalLibraryOrThrow;
+          generateConstants(extension, canonicalLibrary);
+          generateInstanceMethods(extension, canonicalLibrary);
+          generateInstanceOperators(extension, canonicalLibrary);
+          generateInstanceProperties(extension, canonicalLibrary);
+          generateStaticMethods(extension, canonicalLibrary);
+          generateStaticProperties(extension, canonicalLibrary);
         }
 
-        for (var extensionType in lib.extensionTypes.whereDocumented) {
+        for (var extensionType in lib.extensionTypes.whereDocumentedIn(lib)) {
           indexAccumulator.add(extensionType);
           _generatorBackend.generateExtensionType(
               packageGraph, lib, extensionType);
 
-          generateConstants(extensionType);
-          generateConstructors(extensionType);
-          generateInstanceMethods(extensionType);
-          generateInstanceOperators(extensionType);
-          generateInstanceProperties(extensionType);
-          generateStaticMethods(extensionType);
-          generateStaticProperties(extensionType);
+          var canonicalLibrary = extensionType.canonicalLibraryOrThrow;
+          generateConstants(extensionType, canonicalLibrary);
+          generateConstructors(extensionType, canonicalLibrary);
+          generateInstanceMethods(extensionType, canonicalLibrary);
+          generateInstanceOperators(extensionType, canonicalLibrary);
+          generateInstanceProperties(extensionType, canonicalLibrary);
+          generateStaticMethods(extensionType, canonicalLibrary);
+          generateStaticProperties(extensionType, canonicalLibrary);
         }
 
-        for (var mixin in lib.mixins.whereDocumented) {
+        for (var mixin in lib.mixins.whereDocumentedIn(lib)) {
           indexAccumulator.add(mixin);
           _generatorBackend.generateMixin(packageGraph, lib, mixin);
 
-          generateConstants(mixin);
-          generateInstanceMethods(mixin);
-          generateInstanceOperators(mixin);
-          generateInstanceProperties(mixin);
-          generateStaticMethods(mixin);
-          generateStaticProperties(mixin);
+          var canonicalLibrary = mixin.canonicalLibraryOrThrow;
+          generateConstants(mixin, canonicalLibrary);
+          generateInstanceMethods(mixin, canonicalLibrary);
+          generateInstanceOperators(mixin, canonicalLibrary);
+          generateInstanceProperties(mixin, canonicalLibrary);
+          generateStaticMethods(mixin, canonicalLibrary);
+          generateStaticProperties(mixin, canonicalLibrary);
         }
 
-        for (var enum_ in lib.enums.whereDocumented) {
+        for (var enum_ in lib.enums.whereDocumentedIn(lib)) {
           indexAccumulator.add(enum_);
           _generatorBackend.generateEnum(packageGraph, lib, enum_);
 
-          generateConstants(enum_);
-          generateConstructors(enum_);
-          generateInstanceMethods(enum_);
-          generateInstanceOperators(enum_);
-          generateInstanceProperties(enum_);
-          generateStaticMethods(enum_);
-          generateStaticProperties(enum_);
+          var canonicalLibrary = enum_.canonicalLibraryOrThrow;
+          generateConstants(enum_, canonicalLibrary);
+          generateConstructors(enum_, canonicalLibrary);
+          generateInstanceMethods(enum_, canonicalLibrary);
+          generateInstanceOperators(enum_, canonicalLibrary);
+          generateInstanceProperties(enum_, canonicalLibrary);
+          generateStaticMethods(enum_, canonicalLibrary);
+          generateStaticProperties(enum_, canonicalLibrary);
         }
 
-        for (var constant in lib.constants.whereDocumented) {
+        for (var constant in lib.constants.whereDocumentedIn(lib)) {
           indexAccumulator.add(constant);
           _generatorBackend.generateTopLevelProperty(
               packageGraph, lib, constant);
         }
 
-        for (var property in lib.properties.whereDocumented) {
+        for (var property in lib.properties.whereDocumentedIn(lib)) {
           indexAccumulator.add(property);
           _generatorBackend.generateTopLevelProperty(
               packageGraph, lib, property);
         }
 
-        for (var function in lib.functions.whereDocumented) {
+        for (var function in lib.functions.whereDocumentedIn(lib)) {
           indexAccumulator.add(function);
           _generatorBackend.generateFunction(packageGraph, lib, function);
         }
 
-        for (var typeDef in lib.typedefs.whereDocumented) {
+        for (var typeDef in lib.typedefs.whereDocumentedIn(lib)) {
           indexAccumulator.add(typeDef);
           _generatorBackend.generateTypeDef(packageGraph, lib, typeDef);
         }
diff --git a/lib/src/generator/generator_utils.dart b/lib/src/generator/generator_utils.dart
index 94c4c9aef5..907a82f5cc 100644
--- a/lib/src/generator/generator_utils.dart
+++ b/lib/src/generator/generator_utils.dart
@@ -7,6 +7,7 @@ import 'dart:convert';
 import 'package:collection/collection.dart';
 import 'package:dartdoc/src/model/directives/categorization.dart';
 import 'package:dartdoc/src/model/indexable.dart';
+import 'package:dartdoc/src/model/library.dart';
 import 'package:dartdoc/src/model/model_element.dart';
 
 String generateCategoryJson(Iterable<Categorization> categories, bool pretty) {
@@ -15,7 +16,7 @@ String generateCategoryJson(Iterable<Categorization> categories, bool pretty) {
         in categories.sorted(_compareElementRepresentations))
       <String, Object?>{
         'name': categorization.name,
-        'qualifiedName': categorization.fullyQualifiedName,
+        'qualifiedName': categorization.canonicalQualifiedName,
         'href': categorization.href,
         // TODO(srawlins): Rename to 'kind'.
         'type': categorization.kind.toString(),
@@ -42,7 +43,7 @@ String generateSearchIndexJson(Iterable<Indexable> indexedElements,
     for (final item in indexedElements.sorted(_compareElementRepresentations))
       {
         'name': item.name,
-        'qualifiedName': item.fullyQualifiedName,
+        'qualifiedName': item.canonicalQualifiedName,
         'href': item.href,
         'kind': item.kind.index,
         // TODO(srawlins): Only include this for [Inheritable] items.
@@ -112,9 +113,24 @@ final _htmlTagPattern =
 
 // Compares two elements, first by fully qualified name, then by kind.
 int _compareElementRepresentations(Indexable a, Indexable b) {
-  final value = compareNatural(a.fullyQualifiedName, b.fullyQualifiedName);
+  final value =
+      compareNatural(a.canonicalQualifiedName, b.canonicalQualifiedName);
   if (value == 0) {
     return compareNatural(a.kind.toString(), b.kind.toString());
   }
   return value;
 }
+
+extension on Indexable {
+  /// The fully qualified name of this element, but using the canonical library,
+  /// if it has one.
+  String get canonicalQualifiedName {
+    var self = this;
+    if (self is Library) return name;
+    if (self is ModelElement) {
+      var library = self.canonicalLibrary ?? self.library;
+      return '${library.name}.${self.qualifiedName}';
+    }
+    return name;
+  }
+}
diff --git a/lib/src/generator/templates.runtime_renderers.dart b/lib/src/generator/templates.runtime_renderers.dart
index 83df2b9adb..a054eb4405 100644
--- a/lib/src/generator/templates.runtime_renderers.dart
+++ b/lib/src/generator/templates.runtime_renderers.dart
@@ -1128,28 +1128,6 @@ class _Renderer_Category extends RendererBase<Category> {
                         parent: r);
                   },
                 ),
-                'fullyQualifiedName': Property(
-                  getValue: (CT_ c) => c.fullyQualifiedName,
-                  renderVariable:
-                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
-                    if (remainingNames.isEmpty) {
-                      return self.getValue(c).toString();
-                    }
-                    var name = remainingNames.first;
-                    var nextProperty =
-                        _Renderer_String.propertyMap().getValue(name);
-                    return nextProperty.renderVariable(
-                        self.getValue(c) as String,
-                        nextProperty,
-                        [...remainingNames.skip(1)]);
-                  },
-                  isNullValue: (CT_ c) => false,
-                  renderValue: (CT_ c, RendererBase<CT_> r,
-                      List<MustachioNode> ast, StringSink sink) {
-                    _render_String(c.fullyQualifiedName, ast, r.template, sink,
-                        parent: r);
-                  },
-                ),
                 'functions': Property(
                   getValue: (CT_ c) => c.functions,
                   renderVariable: (CT_ c, Property<CT_> self,
@@ -2114,28 +2092,6 @@ class _Renderer_Constructor extends RendererBase<Constructor> {
                         parent: r);
                   },
                 ),
-                'filePath': Property(
-                  getValue: (CT_ c) => c.filePath,
-                  renderVariable:
-                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
-                    if (remainingNames.isEmpty) {
-                      return self.getValue(c).toString();
-                    }
-                    var name = remainingNames.first;
-                    var nextProperty =
-                        _Renderer_String.propertyMap().getValue(name);
-                    return nextProperty.renderVariable(
-                        self.getValue(c) as String,
-                        nextProperty,
-                        [...remainingNames.skip(1)]);
-                  },
-                  isNullValue: (CT_ c) => false,
-                  renderValue: (CT_ c, RendererBase<CT_> r,
-                      List<MustachioNode> ast, StringSink sink) {
-                    _render_String(c.filePath, ast, r.template, sink,
-                        parent: r);
-                  },
-                ),
                 'fullKind': Property(
                   getValue: (CT_ c) => c.fullKind,
                   renderVariable:
@@ -3405,6 +3361,28 @@ class _Renderer_ContainerMember extends RendererBase<ContainerMember> {
                         parent: r);
                   },
                 ),
+                'filePath': Property(
+                  getValue: (CT_ c) => c.filePath,
+                  renderVariable:
+                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
+                    if (remainingNames.isEmpty) {
+                      return self.getValue(c).toString();
+                    }
+                    var name = remainingNames.first;
+                    var nextProperty =
+                        _Renderer_String.propertyMap().getValue(name);
+                    return nextProperty.renderVariable(
+                        self.getValue(c) as String,
+                        nextProperty,
+                        [...remainingNames.skip(1)]);
+                  },
+                  isNullValue: (CT_ c) => false,
+                  renderValue: (CT_ c, RendererBase<CT_> r,
+                      List<MustachioNode> ast, StringSink sink) {
+                    _render_String(c.filePath, ast, r.template, sink,
+                        parent: r);
+                  },
+                ),
                 'isExtended': Property(
                   getValue: (CT_ c) => c.isExtended,
                   renderVariable: (CT_ c, Property<CT_> self,
@@ -5771,28 +5749,6 @@ class _Renderer_Field extends RendererBase<Field> {
                         parent: r);
                   },
                 ),
-                'filePath': Property(
-                  getValue: (CT_ c) => c.filePath,
-                  renderVariable:
-                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
-                    if (remainingNames.isEmpty) {
-                      return self.getValue(c).toString();
-                    }
-                    var name = remainingNames.first;
-                    var nextProperty =
-                        _Renderer_String.propertyMap().getValue(name);
-                    return nextProperty.renderVariable(
-                        self.getValue(c) as String,
-                        nextProperty,
-                        [...remainingNames.skip(1)]);
-                  },
-                  isNullValue: (CT_ c) => false,
-                  renderValue: (CT_ c, RendererBase<CT_> r,
-                      List<MustachioNode> ast, StringSink sink) {
-                    _render_String(c.filePath, ast, r.template, sink,
-                        parent: r);
-                  },
-                ),
                 'fullkind': Property(
                   getValue: (CT_ c) => c.fullkind,
                   renderVariable:
@@ -9195,28 +9151,6 @@ class _Renderer_Method extends RendererBase<Method> {
                         parent: r);
                   },
                 ),
-                'filePath': Property(
-                  getValue: (CT_ c) => c.filePath,
-                  renderVariable:
-                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
-                    if (remainingNames.isEmpty) {
-                      return self.getValue(c).toString();
-                    }
-                    var name = remainingNames.first;
-                    var nextProperty =
-                        _Renderer_String.propertyMap().getValue(name);
-                    return nextProperty.renderVariable(
-                        self.getValue(c) as String,
-                        nextProperty,
-                        [...remainingNames.skip(1)]);
-                  },
-                  isNullValue: (CT_ c) => false,
-                  renderValue: (CT_ c, RendererBase<CT_> r,
-                      List<MustachioNode> ast, StringSink sink) {
-                    _render_String(c.filePath, ast, r.template, sink,
-                        parent: r);
-                  },
-                ),
                 'fullkind': Property(
                   getValue: (CT_ c) => c.fullkind,
                   renderVariable:
@@ -10066,6 +10000,29 @@ class _Renderer_ModelElement extends RendererBase<ModelElement> {
                         parent: r);
                   },
                 ),
+                'canonicalLibraryOrThrow': Property(
+                  getValue: (CT_ c) => c.canonicalLibraryOrThrow,
+                  renderVariable:
+                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
+                    if (remainingNames.isEmpty) {
+                      return self.getValue(c).toString();
+                    }
+                    var name = remainingNames.first;
+                    var nextProperty =
+                        _Renderer_Library.propertyMap().getValue(name);
+                    return nextProperty.renderVariable(
+                        self.getValue(c) as Library,
+                        nextProperty,
+                        [...remainingNames.skip(1)]);
+                  },
+                  isNullValue: (CT_ c) => false,
+                  renderValue: (CT_ c, RendererBase<CT_> r,
+                      List<MustachioNode> ast, StringSink sink) {
+                    _render_Library(
+                        c.canonicalLibraryOrThrow, ast, r.template, sink,
+                        parent: r);
+                  },
+                ),
                 'canonicalModelElement': Property(
                   getValue: (CT_ c) => c.canonicalModelElement,
                   renderVariable:
@@ -10132,28 +10089,6 @@ class _Renderer_ModelElement extends RendererBase<ModelElement> {
                         getters: _invisibleGetters['DartdocOptionContext']!);
                   },
                 ),
-                'definingLibrary': Property(
-                  getValue: (CT_ c) => c.definingLibrary,
-                  renderVariable:
-                      (CT_ c, Property<CT_> self, List<String> remainingNames) {
-                    if (remainingNames.isEmpty) {
-                      return self.getValue(c).toString();
-                    }
-                    var name = remainingNames.first;
-                    var nextProperty =
-                        _Renderer_Library.propertyMap().getValue(name);
-                    return nextProperty.renderVariable(
-                        self.getValue(c) as Library,
-                        nextProperty,
-                        [...remainingNames.skip(1)]);
-                  },
-                  isNullValue: (CT_ c) => false,
-                  renderValue: (CT_ c, RendererBase<CT_> r,
-                      List<MustachioNode> ast, StringSink sink) {
-                    _render_Library(c.definingLibrary, ast, r.template, sink,
-                        parent: r);
-                  },
-                ),
                 'displayedCategories': Property(
                   getValue: (CT_ c) => c.displayedCategories,
                   renderVariable: (CT_ c, Property<CT_> self,
@@ -12203,7 +12138,7 @@ class _Renderer_Package extends RendererBase<Package> {
   }
 }
 
-String renderError(PackageTemplateData context, Template template) {
+String renderSearchPage(PackageTemplateData context, Template template) {
   var buffer = StringBuffer();
   _render_PackageTemplateData(context, template.ast, template, buffer);
   return buffer.toString();
@@ -12447,7 +12382,7 @@ String renderIndex(PackageTemplateData context, Template template) {
   return buffer.toString();
 }
 
-String renderSearchPage(PackageTemplateData context, Template template) {
+String renderError(PackageTemplateData context, Template template) {
   var buffer = StringBuffer();
   _render_PackageTemplateData(context, template.ast, template, buffer);
   return buffer.toString();
diff --git a/lib/src/model/canonicalization.dart b/lib/src/model/canonicalization.dart
index 61121ca229..e51805ff11 100644
--- a/lib/src/model/canonicalization.dart
+++ b/lib/src/model/canonicalization.dart
@@ -5,7 +5,7 @@
 import 'package:dartdoc/src/model/model.dart';
 import 'package:dartdoc/src/warnings.dart';
 
-/// Classes extending this class have canonicalization support in Dartdoc.
+/// Canonicalization support in Dartdoc.
 ///
 /// This provides heuristic scoring to determine which library a human likely
 /// considers this element to be primarily 'from', and therefore, canonical.
@@ -15,6 +15,7 @@ final class Canonicalization {
 
   Canonicalization(this._element);
 
+  /// Calculates a candidate for the canonical library of [_element], among [libraries].
   Library calculateCanonicalCandidate(Iterable<Library> libraries) {
     var locationPieces = _element.element.location
         .toString()
diff --git a/lib/src/model/category.dart b/lib/src/model/category.dart
index 4a15d64d53..f2081eb62b 100644
--- a/lib/src/model/category.dart
+++ b/lib/src/model/category.dart
@@ -21,6 +21,8 @@ class Category
         TopLevelContainer,
         Indexable
     implements Documentable {
+  /// The package in which this category is contained.
+  ///
   /// All libraries in [libraries] must come from [package].
   @override
   final Package package;
@@ -103,9 +105,6 @@ class Category
   late final bool isDocumented =
       documentedWhere != DocumentLocation.missing && documentationFile != null;
 
-  @override
-  String get fullyQualifiedName => name;
-
   String get filePath => 'topics/$name-topic.html';
 
   @override
diff --git a/lib/src/model/class.dart b/lib/src/model/class.dart
index 23df4ee4cf..acbbb19a0a 100644
--- a/lib/src/model/class.dart
+++ b/lib/src/model/class.dart
@@ -23,7 +23,8 @@ class Class extends InheritingContainer with Constructable, MixedInTypes {
   ];
 
   @override
-  String get sidebarPath => '${library.dirName}/$name-class-sidebar.html';
+  String get sidebarPath =>
+      '${canonicalLibraryOrThrow.dirName}/$name-class-sidebar.html';
 
   @override
   late final List<InheritingContainer> inheritanceChain = [
diff --git a/lib/src/model/constructor.dart b/lib/src/model/constructor.dart
index 94b229cdf5..f9ab062554 100644
--- a/lib/src/model/constructor.dart
+++ b/lib/src/model/constructor.dart
@@ -55,10 +55,6 @@ class Constructor extends ModelElement with ContainerMember, TypeParameters {
   Container get enclosingElement =>
       getModelFor(element.enclosingElement, library) as Container;
 
-  @override
-  String get filePath =>
-      '${enclosingElement.library.dirName}/${enclosingElement.name}/$fileName';
-
   @override
   String get aboveSidebarPath => enclosingElement.sidebarPath;
 
diff --git a/lib/src/model/container.dart b/lib/src/model/container.dart
index 644381b5ea..a4ace6017e 100644
--- a/lib/src/model/container.dart
+++ b/lib/src/model/container.dart
@@ -229,10 +229,10 @@ abstract class Container extends ModelElement
   };
 
   @override
-  Iterable<CommentReferable> get referenceParents => [definingLibrary, library];
+  Iterable<CommentReferable> get referenceParents => [library];
 
   @override
-  String get filePath => '${library.dirName}/$fileName';
+  String get filePath => '${canonicalLibraryOrThrow.dirName}/$fileName';
 
   /// The full path of this element's sidebar file.
   String get sidebarPath;
diff --git a/lib/src/model/container_member.dart b/lib/src/model/container_member.dart
index 80e54eae6a..8480ed5f5a 100644
--- a/lib/src/model/container_member.dart
+++ b/lib/src/model/container_member.dart
@@ -21,6 +21,10 @@ mixin ContainerMember on ModelElement {
   @override
   Container get enclosingElement;
 
+  @override
+  String get filePath =>
+      '${canonicalLibraryOrThrow.dirName}/${enclosingElement.name}/$fileName';
+
   /// The container that contains this member.
   @protected
   @visibleForTesting
@@ -60,7 +64,7 @@ mixin ContainerMember on ModelElement {
       // and resolve the pieces with different scopes.  dart-lang/dartdoc#2693.
       // Until then, just pretend we're handling this correctly.
       [
-        (documentationFrom.first as ModelElement).definingLibrary,
+        (documentationFrom.first as ModelElement).library,
         if (this case Field(:var getter, :var setter))
           packageGraph.findCanonicalModelElementFor(getter ?? setter)?.library
         else
diff --git a/lib/src/model/documentation_comment.dart b/lib/src/model/documentation_comment.dart
index 35dbb5ef95..cbbd350e7f 100644
--- a/lib/src/model/documentation_comment.dart
+++ b/lib/src/model/documentation_comment.dart
@@ -9,6 +9,7 @@ import 'package:dartdoc/src/model/documentable.dart';
 import 'package:dartdoc/src/model/documentation.dart';
 import 'package:dartdoc/src/model/inheritable.dart';
 import 'package:dartdoc/src/model/locatable.dart';
+import 'package:dartdoc/src/model/model_element.dart';
 import 'package:dartdoc/src/model/source_code_mixin.dart';
 import 'package:dartdoc/src/utils.dart';
 import 'package:dartdoc/src/warnings.dart';
@@ -273,6 +274,10 @@ mixin DocumentationComment
 
   /// The environment variables to use when running a tool.
   Map<String, String> _toolsEnvironment({required int invocationIndex}) {
+    var self = this;
+    var library = self is ModelElement
+        ? (self.canonicalLibrary ?? this.library)
+        : this.library;
     var env = {
       'SOURCE_LINE': characterLocation?.lineNumber.toString(),
       'SOURCE_COLUMN': characterLocation?.columnNumber.toString(),
diff --git a/lib/src/model/enum.dart b/lib/src/model/enum.dart
index 84e2701f92..914240b258 100644
--- a/lib/src/model/enum.dart
+++ b/lib/src/model/enum.dart
@@ -31,7 +31,8 @@ class Enum extends InheritingContainer with Constructable, MixedInTypes {
   ];
 
   @override
-  String get sidebarPath => '${library.dirName}/$name-enum-sidebar.html';
+  String get sidebarPath =>
+      '${canonicalLibraryOrThrow.dirName}/$name-enum-sidebar.html';
 
   @override
   Kind get kind => Kind.enum_;
@@ -110,7 +111,6 @@ class EnumField extends Field {
     if (!identical(canonicalModelElement, this)) {
       return canonicalModelElement?.href;
     }
-    assert(canonicalLibrary == library);
     assert(canonicalEnclosingContainer == enclosingElement);
     // TODO(jcollins-g): EnumField should not depend on enclosingElement, but
     // we sort of have to while we are half-converted to [FileStructure].
diff --git a/lib/src/model/extension.dart b/lib/src/model/extension.dart
index f32b03374f..4d501bb1b2 100644
--- a/lib/src/model/extension.dart
+++ b/lib/src/model/extension.dart
@@ -93,7 +93,8 @@ class Extension extends Container {
   ];
 
   @override
-  String get sidebarPath => '${library.dirName}/$name-extension-sidebar.html';
+  String get sidebarPath =>
+      '${canonicalLibraryOrThrow.dirName}/$name-extension-sidebar.html';
 
   Map<String, CommentReferable>? _referenceChildren;
   @override
diff --git a/lib/src/model/extension_type.dart b/lib/src/model/extension_type.dart
index f463efe3b7..3a50e9ee13 100644
--- a/lib/src/model/extension_type.dart
+++ b/lib/src/model/extension_type.dart
@@ -70,7 +70,7 @@ class ExtensionType extends InheritingContainer with Constructable {
 
   @override
   String get sidebarPath =>
-      '${library.dirName}/$name-extension-type-sidebar.html';
+      '${canonicalLibraryOrThrow.dirName}/$name-extension-type-sidebar.html';
 
   Map<String, CommentReferable>? _referenceChildren;
   @override
diff --git a/lib/src/model/field.dart b/lib/src/model/field.dart
index 27c4a87275..afe87bda33 100644
--- a/lib/src/model/field.dart
+++ b/lib/src/model/field.dart
@@ -76,10 +76,6 @@ class Field extends ModelElement
     return super.documentation;
   }
 
-  @override
-  String get filePath =>
-      '${enclosingElement.library.dirName}/${enclosingElement.name}/$fileName';
-
   @override
   String? get href {
     assert(!identical(canonicalModelElement, this) ||
diff --git a/lib/src/model/inheritable.dart b/lib/src/model/inheritable.dart
index e671dc147b..6979abeeff 100644
--- a/lib/src/model/inheritable.dart
+++ b/lib/src/model/inheritable.dart
@@ -86,19 +86,6 @@ mixin Inheritable on ContainerMember {
           previousNonSkippable = c;
         }
       }
-      // This is still OK because we're never supposed to cloak public
-      // classes.
-      if (definingEnclosingContainer.isCanonical &&
-          definingEnclosingContainer.isPublic) {
-        assert(
-            definingEnclosingContainer == found,
-            "For '$element' (${element.hashCode}) "
-            "(search element: '$searchElement', ${searchElement?.hashCode}, in "
-            "'${searchElement?.enclosingElement}'), expected "
-            "'$definingEnclosingContainer', which is canonical, to be '$found',"
-            "but was not. Here's the inheritance chain: "
-            '${inheritance.reversed}.');
-      }
       if (found != null) {
         return found;
       }
diff --git a/lib/src/model/inheriting_container.dart b/lib/src/model/inheriting_container.dart
index 018273459f..98a9df6fa6 100644
--- a/lib/src/model/inheriting_container.dart
+++ b/lib/src/model/inheriting_container.dart
@@ -288,7 +288,7 @@ abstract class InheritingContainer extends Container {
 
   /// The [InheritingContainer] with the library in which [element] is defined.
   InheritingContainer get definingContainer =>
-      getModelFor(element, definingLibrary) as InheritingContainer;
+      getModelFor(element, library) as InheritingContainer;
 
   @override
   InterfaceElement get element;
diff --git a/lib/src/model/library.dart b/lib/src/model/library.dart
index b58301d2ad..ac8a50d31b 100644
--- a/lib/src/model/library.dart
+++ b/lib/src/model/library.dart
@@ -21,7 +21,13 @@ class Library extends ModelElement
   @override
   final LibraryElement element;
 
-  final Set<Element> _exportedAndLocalElements;
+  /// The set of [Element]s declared directly in this library.
+  final Set<Element> _localElements;
+
+  /// The set of [Element]s exported by this library but not directly declared
+  /// in this library.
+  final Set<Element> _exportedElements;
+
   final String _restoredUri;
 
   @override
@@ -40,7 +46,7 @@ class Library extends ModelElement
   static final Library sentinel = _LibrarySentinel();
 
   Library._(this.element, PackageGraph packageGraph, this.package,
-      this._restoredUri, this._exportedAndLocalElements)
+      this._restoredUri, this._localElements, this._exportedElements)
       : super(sentinel, packageGraph);
 
   factory Library.fromLibraryResult(DartDocResolvedLibrary resolvedLibrary,
@@ -49,10 +55,7 @@ class Library extends ModelElement
 
     var element = resolvedLibrary.element;
 
-    var exportedAndLocalElements = {
-      // Initialize the list of elements defined in this library and
-      // exported via its export directives.
-      ...element.exportNamespace.definedNames.values,
+    var localElements = {
       // TODO(jcollins-g): Consider switch to `element.topLevelElements`.
       ..._getDefinedElements(element.definingCompilationUnit),
       ...element.parts
@@ -60,12 +63,16 @@ class Library extends ModelElement
           .whereType<DirectiveUriWithUnit>()
           .map((part) => part.unit)
     };
+    var exportedElements = {...element.exportNamespace.definedNames.values}
+        .difference(localElements);
     var library = Library._(
-        element,
-        packageGraph,
-        package,
-        resolvedLibrary.element.source.uri.toString(),
-        exportedAndLocalElements);
+      element,
+      packageGraph,
+      package,
+      resolvedLibrary.element.source.uri.toString(),
+      localElements,
+      exportedElements,
+    );
 
     package.allLibraries.add(library);
     return library;
@@ -286,19 +293,26 @@ class Library extends ModelElement
   late final PackageMeta? packageMeta =
       packageGraph.packageMetaProvider.fromElement(element, config.sdkDir);
 
-  late final List<Class> classesAndExceptions =
-      _elementsOfType<ClassElement, Class>();
+  late final List<Class> classesAndExceptions = [
+    ..._localElementsOfType<ClassElement, Class>(),
+    ..._exportedElementsOfType<ClassElement, Class>(),
+  ];
 
   @override
   Iterable<Class> get classes =>
       classesAndExceptions.where((c) => !c.isErrorOrException);
 
   @override
-  Iterable<TopLevelVariable> get constants =>
-      _variables.where((v) => v.isConst);
+  late final Iterable<TopLevelVariable> constants = [
+    ..._localVariables.where((v) => v.isConst),
+    ..._exportedVariables.where((v) => v.isConst),
+  ];
 
   @override
-  late final List<Enum> enums = _elementsOfType<EnumElement, Enum>();
+  late final List<Enum> enums = [
+    ..._localElementsOfType<EnumElement, Enum>(),
+    ..._exportedElementsOfType<EnumElement, Enum>(),
+  ];
 
   @override
   late final List<Class> exceptions = classesAndExceptions
@@ -306,59 +320,91 @@ class Library extends ModelElement
       .toList(growable: false);
 
   @override
-  late final List<Extension> extensions =
-      _elementsOfType<ExtensionElement, Extension>();
+  late final List<Extension> extensions = [
+    ..._localElementsOfType<ExtensionElement, Extension>(),
+    ..._exportedElementsOfType<ExtensionElement, Extension>(),
+  ];
 
   @override
-  late final List<ExtensionType> extensionTypes =
-      _elementsOfType<ExtensionTypeElement, ExtensionType>();
+  late final List<ExtensionType> extensionTypes = [
+    ..._localElementsOfType<ExtensionTypeElement, ExtensionType>(),
+    ..._exportedElementsOfType<ExtensionTypeElement, ExtensionType>(),
+  ];
 
   @override
-  late final List<ModelFunction> functions =
-      _elementsOfType<FunctionElement, ModelFunction>();
+  late final List<ModelFunction> functions = [
+    ..._localElementsOfType<FunctionElement, ModelFunction>(),
+    ..._exportedElementsOfType<FunctionElement, ModelFunction>(),
+  ];
 
   @override
-  late final List<Mixin> mixins = _elementsOfType<MixinElement, Mixin>();
+  late final List<Mixin> mixins = [
+    ..._localElementsOfType<MixinElement, Mixin>(),
+    ..._exportedElementsOfType<MixinElement, Mixin>(),
+  ];
 
   @override
-  late final List<TopLevelVariable> properties =
-      _variables.where((v) => !v.isConst).toList(growable: false);
+  late final List<TopLevelVariable> properties = [
+    ..._localVariables.where((v) => !v.isConst),
+    ..._exportedVariables.where((v) => !v.isConst),
+  ];
 
   @override
-  late final List<Typedef> typedefs =
-      _elementsOfType<TypeAliasElement, Typedef>();
-
-  List<U> _elementsOfType<T extends Element, U extends ModelElement>() =>
-      _exportedAndLocalElements
-          .whereType<T>()
-          .map((e) => packageGraph.getModelFor(e, this) as U)
-          .toList(growable: false);
-
-  /// All top-level variables, including "properties" and constants.
-  List<TopLevelVariable> get _variables {
-    var elements = {
-      ..._exportedAndLocalElements.whereType<TopLevelVariableElement>(),
-      ..._exportedAndLocalElements
+  late final List<Typedef> typedefs = [
+    ..._localElementsOfType<TypeAliasElement, Typedef>(),
+    ..._exportedElementsOfType<TypeAliasElement, Typedef>(),
+  ];
+
+  Iterable<U>
+      _localElementsOfType<T extends Element, U extends ModelElement>() =>
+          _localElements
+              .whereType<T>()
+              .map((e) => packageGraph.getModelFor(e, this) as U);
+
+  Iterable<U>
+      _exportedElementsOfType<T extends Element, U extends ModelElement>() =>
+          _exportedElements.whereType<T>().map((e) {
+            var library = e.library;
+            if (library == null) {
+              throw StateError("The library of '$e' is null!");
+            }
+            return packageGraph.getModelFor(
+              e,
+              packageGraph.getModelForElement(library) as Library,
+            ) as U;
+          });
+
+  Iterable<TopLevelVariable> get _localVariables {
+    return {
+      ..._localElements.whereType<TopLevelVariableElement>(),
+      ..._localElements
           .whereType<PropertyAccessorElement>()
-          .map((a) => a.variable2! as TopLevelVariableElement)
-    };
-    var variables = <TopLevelVariable>[];
-    for (var element in elements) {
-      Accessor? getter;
-      var elementGetter = element.getter;
-      if (elementGetter != null) {
-        getter = packageGraph.getModelFor(elementGetter, this) as Accessor;
-      }
-      Accessor? setter;
-      var elementSetter = element.setter;
-      if (elementSetter != null) {
-        setter = packageGraph.getModelFor(elementSetter, this) as Accessor;
-      }
-      var me = getModelForPropertyInducingElement(element, this,
-          getter: getter, setter: setter);
-      variables.add(me as TopLevelVariable);
+          .map((a) => a.variable2! as TopLevelVariableElement),
+    }.map(_topLevelVariableFor);
+  }
+
+  Iterable<TopLevelVariable> get _exportedVariables {
+    return {
+      ..._exportedElements.whereType<TopLevelVariableElement>(),
+      ..._exportedElements
+          .whereType<PropertyAccessorElement>()
+          .map((a) => a.variable2! as TopLevelVariableElement),
+    }.map(_topLevelVariableFor);
+  }
+
+  TopLevelVariable _topLevelVariableFor(TopLevelVariableElement element) {
+    Accessor? getter;
+    var elementGetter = element.getter;
+    if (elementGetter != null) {
+      getter = packageGraph.getModelFor(elementGetter, this) as Accessor;
+    }
+    Accessor? setter;
+    var elementSetter = element.setter;
+    if (elementSetter != null) {
+      setter = packageGraph.getModelFor(elementSetter, this) as Accessor;
     }
-    return variables;
+    return getModelForPropertyInducingElement(element, this,
+        getter: getter, setter: setter) as TopLevelVariable;
   }
 
   /// All [ModelElement]s, direct and indirect, which are part of this library's
diff --git a/lib/src/model/method.dart b/lib/src/model/method.dart
index 0f1537d925..9f6e4012e3 100644
--- a/lib/src/model/method.dart
+++ b/lib/src/model/method.dart
@@ -58,10 +58,6 @@ class Method extends ModelElement
   Container get enclosingElement => _enclosingContainer ??=
       getModelFor(element.enclosingElement, library) as Container;
 
-  @override
-  String get filePath =>
-      '${enclosingElement.library.dirName}/${enclosingElement.name}/$fileName';
-
   @override
   String get aboveSidebarPath => enclosingElement.sidebarPath;
 
diff --git a/lib/src/model/mixin.dart b/lib/src/model/mixin.dart
index d6d3fa9263..ab7756bd92 100644
--- a/lib/src/model/mixin.dart
+++ b/lib/src/model/mixin.dart
@@ -27,7 +27,8 @@ class Mixin extends InheritingContainer {
   String get fileName => '$name-mixin.html';
 
   @override
-  String get sidebarPath => '${library.dirName}/$name-mixin-sidebar.html';
+  String get sidebarPath =>
+      '${canonicalLibraryOrThrow.dirName}/$name-mixin-sidebar.html';
 
   @override
   late final List<InheritingContainer> inheritanceChain = [
diff --git a/lib/src/model/model_element.dart b/lib/src/model/model_element.dart
index 753adaed66..0af2b4ce24 100644
--- a/lib/src/model/model_element.dart
+++ b/lib/src/model/model_element.dart
@@ -129,7 +129,7 @@ abstract class ModelElement
 
     // Return the cached ModelElement if it exists.
     var cachedModelElement = packageGraph.allConstructedModelElements[
-        ConstructedModelElementsKey(e, library, enclosingContainer)];
+        ConstructedModelElementsKey(e, enclosingContainer)];
     if (cachedModelElement != null) {
       return cachedModelElement;
     }
@@ -215,7 +215,7 @@ abstract class ModelElement
     }
 
     // Return the cached ModelElement if it exists.
-    var key = ConstructedModelElementsKey(e, library, enclosingContainer);
+    var key = ConstructedModelElementsKey(e, enclosingContainer);
     var cachedModelElement = packageGraph.allConstructedModelElements[key];
     if (cachedModelElement != null) {
       return cachedModelElement;
@@ -256,7 +256,7 @@ abstract class ModelElement
         '$enclosingContainer.library != $library');
     if (library != Library.sentinel && newModelElement is! Parameter) {
       runtimeStats.incrementAccumulator('modelElementCacheInsertion');
-      var key = ConstructedModelElementsKey(e, library, enclosingContainer);
+      var key = ConstructedModelElementsKey(e, enclosingContainer);
       library.packageGraph.allConstructedModelElements[key] = newModelElement;
       if (newModelElement is Inheritable) {
         library.packageGraph.allInheritableElements
@@ -378,9 +378,13 @@ abstract class ModelElement
     if (name.isEmpty) {
       return false;
     }
-    if (this is! Library &&
-        (library == Library.sentinel || !library.isPublic)) {
-      return false;
+    if (this is! Library) {
+      final canonicalLibrary = this.canonicalLibrary;
+      var isLibraryOrCanonicalLibraryPrivate = !library.isPublic &&
+          (canonicalLibrary == null || !canonicalLibrary.isPublic);
+      if (library == Library.sentinel || isLibraryOrCanonicalLibraryPrivate) {
+        return false;
+      }
     }
     if (enclosingElement is Class && !(enclosingElement as Class).isPublic) {
       return false;
@@ -448,15 +452,17 @@ abstract class ModelElement
 
   late final String sourceHref = SourceLinker.fromElement(this).href();
 
-  /// The library in which [element] is declared.
-  ///
-  /// This is different from [library] if this [ModelElement] is derived from
-  /// a library that exports [element] from another library.
-  Library get definingLibrary =>
-      getModelForElement(element.library!) as Library;
+  Library get canonicalLibraryOrThrow {
+    final canonicalLibrary = this.canonicalLibrary;
+    if (canonicalLibrary == null) {
+      throw StateError(
+          "Expected the canonical library of '$fullyQualifiedName' to be non-null.");
+    }
+    return canonicalLibrary;
+  }
 
   /// A public, documented library which exports this [ModelElement], ideally in
-  /// [definingLibrary]'s package.
+  /// [library]'s package.
   late final Library? canonicalLibrary = () {
     if (element.hasPrivateName) {
       // Privately named elements can never have a canonical library.
@@ -467,10 +473,9 @@ abstract class ModelElement
     assert(packageGraph.allLibrariesAdded);
 
     var definingLibraryIsLocalPublic =
-        packageGraph.localPublicLibraries.contains(definingLibrary);
-    var possibleCanonicalLibrary = definingLibraryIsLocalPublic
-        ? definingLibrary
-        : _searchForCanonicalLibrary();
+        packageGraph.localPublicLibraries.contains(library);
+    var possibleCanonicalLibrary =
+        definingLibraryIsLocalPublic ? library : _searchForCanonicalLibrary();
 
     if (possibleCanonicalLibrary != null) return possibleCanonicalLibrary;
 
@@ -488,9 +493,9 @@ abstract class ModelElement
   }();
 
   /// Searches [PackageGraph.libraryExports] for a public, documented library
-  /// which exports this [ModelElement], ideally in [definingLibrary]'s package.
+  /// which exports this [ModelElement], ideally in [library]'s package.
   Library? _searchForCanonicalLibrary() {
-    var thisAndExported = packageGraph.libraryExports[definingLibrary.element];
+    var thisAndExported = packageGraph.libraryExports[library.element];
     if (thisAndExported == null) {
       return null;
     }
@@ -510,10 +515,9 @@ abstract class ModelElement
       return null;
     }
 
-    final candidateLibraries = thisAndExported
-        .where((l) =>
-            l.isPublic && l.package.documentedWhere != DocumentLocation.missing)
-        .where((l) {
+    final candidateLibraries = thisAndExported.where((l) {
+      if (!l.isPublic) return false;
+      if (l.package.documentedWhere == DocumentLocation.missing) return false;
       var lookup = l.element.exportNamespace.definedNames[topLevelElementName];
       return topLevelElement ==
           (lookup is PropertyAccessorElement ? lookup.variable2 : lookup);
@@ -535,7 +539,7 @@ abstract class ModelElement
   @override
   bool get isCanonical {
     if (!isPublic) return false;
-    if (library != canonicalLibrary) return false;
+    if (this is Library && library != canonicalLibrary) return false;
     // If there's no inheritance to deal with, we're done.
     if (this is! Inheritable) return true;
     final self = this as Inheritable;
@@ -574,7 +578,7 @@ abstract class ModelElement
 
   @override
   String get fullyQualifiedName =>
-      this is Library ? qualifiedName : '${library.name}.$qualifiedName';
+      this is Library ? name : '${library.name}.$qualifiedName';
 
   @override
   late final String qualifiedName = () {
@@ -621,7 +625,6 @@ abstract class ModelElement
     if (!identical(canonicalModelElement, this)) {
       return canonicalModelElement?.href;
     }
-    assert(canonicalLibrary == library);
     var packageBaseHref = package.baseHref;
     return '$packageBaseHref$filePath';
   }
diff --git a/lib/src/model/model_function.dart b/lib/src/model/model_function.dart
index d1f777bee4..255e1c319f 100644
--- a/lib/src/model/model_function.dart
+++ b/lib/src/model/model_function.dart
@@ -48,7 +48,7 @@ class ModelFunctionTyped extends ModelElement with TypeParameters {
   Library get enclosingElement => library;
 
   @override
-  String get filePath => '${library.dirName}/$fileName';
+  String get filePath => '${canonicalLibrary?.dirName}/$fileName';
 
   @override
   String get aboveSidebarPath => enclosingElement.sidebarPath;
@@ -61,7 +61,6 @@ class ModelFunctionTyped extends ModelElement with TypeParameters {
     if (!identical(canonicalModelElement, this)) {
       return canonicalModelElement?.href;
     }
-    assert(canonicalLibrary == library);
     return '${package.baseHref}$filePath';
   }
 
@@ -78,7 +77,7 @@ class ModelFunctionTyped extends ModelElement with TypeParameters {
   };
 
   @override
-  Iterable<CommentReferable> get referenceParents => [definingLibrary];
+  Iterable<CommentReferable> get referenceParents => [library];
 
   late final Callable modelType = getTypeFor(element.type, library) as Callable;
 }
diff --git a/lib/src/model/nameable.dart b/lib/src/model/nameable.dart
index b8229554ff..2daffabb6b 100644
--- a/lib/src/model/nameable.dart
+++ b/lib/src/model/nameable.dart
@@ -16,9 +16,8 @@ import 'package:dartdoc/src/model/package_graph.dart';
 mixin Nameable {
   String get name;
 
-  /// A "fully" qualified name, mostly for use in the web search functionality,
-  /// and for warnings printed in the terminal; not for display use in rendered
-  /// HTML.
+  /// A "fully" qualified name, used for things like for warnings printed in the
+  /// terminal; not for display use in rendered HTML.
   ///
   /// "Fully" means the name is qualified through the library. For example, a
   /// method named 'baz' in a class named 'Bar' in a library named 'foo' has a
diff --git a/lib/src/model/package_graph.dart b/lib/src/model/package_graph.dart
index a8663dbd72..07fbf18440 100644
--- a/lib/src/model/package_graph.dart
+++ b/lib/src/model/package_graph.dart
@@ -827,12 +827,12 @@ class PackageGraph with CommentReferable, Nameable {
     var candidates = <ModelElement>{};
     if (lib != null) {
       var constructedWithKey = allConstructedModelElements[
-          ConstructedModelElementsKey(element, lib, null)];
+          ConstructedModelElementsKey(element, null)];
       if (constructedWithKey != null) {
         candidates.add(constructedWithKey);
       }
       var constructedWithKeyWithClass = allConstructedModelElements[
-          ConstructedModelElementsKey(element, lib, preferredClass)];
+          ConstructedModelElementsKey(element, preferredClass)];
       if (constructedWithKeyWithClass != null) {
         candidates.add(constructedWithKeyWithClass);
       }
@@ -1044,20 +1044,17 @@ class PackageGraph with CommentReferable, Nameable {
 
 class ConstructedModelElementsKey {
   final Element element;
-  final Library library;
   final Container? enclosingElement;
 
-  ConstructedModelElementsKey(
-      this.element, this.library, this.enclosingElement);
+  ConstructedModelElementsKey(this.element, this.enclosingElement);
 
   @override
-  late final int hashCode = Object.hash(element, library, enclosingElement);
+  late final int hashCode = Object.hash(element, enclosingElement);
 
   @override
   bool operator ==(Object other) {
     if (other is! ConstructedModelElementsKey) return false;
     return other.element == element &&
-        other.library == library &&
         other.enclosingElement == enclosingElement;
   }
 }
diff --git a/lib/src/model/prefix.dart b/lib/src/model/prefix.dart
index 9c4d6d6881..e048a3a5f4 100644
--- a/lib/src/model/prefix.dart
+++ b/lib/src/model/prefix.dart
@@ -48,5 +48,5 @@ class Prefix extends ModelElement with HasNoPage {
   Map<String, CommentReferable> get referenceChildren => {};
 
   @override
-  Iterable<CommentReferable> get referenceParents => [definingLibrary];
+  Iterable<CommentReferable> get referenceParents => [library];
 }
diff --git a/lib/src/model/top_level_variable.dart b/lib/src/model/top_level_variable.dart
index 6d90674bab..cc10f58daa 100644
--- a/lib/src/model/top_level_variable.dart
+++ b/lib/src/model/top_level_variable.dart
@@ -42,7 +42,7 @@ class TopLevelVariable extends ModelElement
   Library get enclosingElement => library;
 
   @override
-  String get filePath => '${library.dirName}/$fileName';
+  String get filePath => '${canonicalLibraryOrThrow.dirName}/$fileName';
 
   @override
   String get aboveSidebarPath => enclosingElement.sidebarPath;
@@ -55,7 +55,6 @@ class TopLevelVariable extends ModelElement
     if (!identical(canonicalModelElement, this)) {
       return canonicalModelElement?.href;
     }
-    assert(canonicalLibrary == library);
     return '${package.baseHref}$filePath';
   }
 
@@ -80,5 +79,5 @@ class TopLevelVariable extends ModelElement
   Set<Attribute> get attributes => {...super.attributes, ...comboAttributes};
 
   @override
-  Iterable<CommentReferable> get referenceParents => [definingLibrary];
+  Iterable<CommentReferable> get referenceParents => [library];
 }
diff --git a/lib/src/model/typedef.dart b/lib/src/model/typedef.dart
index 899cd59ced..e245371fb2 100644
--- a/lib/src/model/typedef.dart
+++ b/lib/src/model/typedef.dart
@@ -32,7 +32,7 @@ abstract class Typedef extends ModelElement
   String get linkedGenericParameters => _renderTypeParameters(isLinked: true);
 
   @override
-  String get filePath => '${library.dirName}/$fileName';
+  String get filePath => '${canonicalLibraryOrThrow.dirName}/$fileName';
 
   @override
   String get aboveSidebarPath => enclosingElement.sidebarPath;
@@ -49,7 +49,6 @@ abstract class Typedef extends ModelElement
     if (!identical(canonicalModelElement, this)) {
       return canonicalModelElement?.href;
     }
-    assert(canonicalLibrary == library);
     return '${package.baseHref}$filePath';
   }
 
@@ -65,7 +64,7 @@ abstract class Typedef extends ModelElement
       .toList(growable: false);
 
   @override
-  Iterable<CommentReferable> get referenceParents => [definingLibrary];
+  Iterable<CommentReferable> get referenceParents => [library];
 
   late final Map<String, CommentReferable> _referenceChildren = {
     ...typeParameters.explicitOnCollisionWith(this),
diff --git a/lib/src/model_utils.dart b/lib/src/model_utils.dart
index 10a617884b..9d73320dd0 100644
--- a/lib/src/model_utils.dart
+++ b/lib/src/model_utils.dart
@@ -98,3 +98,9 @@ extension IterableOfDocumentableExtension<E extends Documentable>
 extension IterableOfNameableExtension<E extends Nameable> on Iterable<E> {
   Iterable<E> get wherePublic => where((e) => e.isPublic);
 }
+
+extension IterableOfModelElementExtension<E extends ModelElement>
+    on Iterable<E> {
+  Iterable<E> whereDocumentedIn(Library library) =>
+      whereDocumented.where((e) => e.canonicalLibrary == library);
+}
diff --git a/test/end2end/model_special_cases_test.dart b/test/end2end/model_special_cases_test.dart
index aad403fd67..3f085cbbc2 100644
--- a/test/end2end/model_special_cases_test.dart
+++ b/test/end2end/model_special_cases_test.dart
@@ -370,27 +370,6 @@ void main() {
       expect(IAmAClassWithCategories.displayedCategories, isEmpty);
     });
 
-    // For flutter, we allow reexports to pick up categories from the package
-    // they are exposed in.
-    test('Verify that reexported classes pick up categories', () {
-      var IAmAClassWithCategoriesReexport = ginormousPackageGraph.localPackages
-          .firstWhere((p) => p.name == 'test_package')
-          .libraries
-          .wherePublic
-          .named('fake')
-          .classes
-          .wherePublic
-          .named('IAmAClassWithCategories');
-      expect(IAmAClassWithCategoriesReexport.hasCategoryNames, isTrue);
-      expect(IAmAClassWithCategoriesReexport.categories, hasLength(1));
-      expect(IAmAClassWithCategoriesReexport.categories.first.name,
-          equals('Superb'));
-      expect(IAmAClassWithCategoriesReexport.displayedCategories, isNotEmpty);
-      var category = IAmAClassWithCategoriesReexport.displayedCategories.first;
-      expect(category.categoryIndex, equals(0));
-      expect(category.isDocumented, isTrue);
-    });
-
     test('Verify that multiple categories work correctly', () {
       var fakeLibrary = ginormousPackageGraph.localPackages
           .firstWhere((p) => p.name == 'test_package')
diff --git a/test/end2end/model_test.dart b/test/end2end/model_test.dart
index 5af9cef3e6..a4ec522094 100644
--- a/test/end2end/model_test.dart
+++ b/test/end2end/model_test.dart
@@ -520,46 +520,26 @@ void main() async {
 
   group('Tools', () {
     late final Class toolUser;
-    late final Class NonCanonicalToolUser,
-        CanonicalToolUser,
-        PrivateLibraryToolUser;
     late final Class ImplementingClassForTool,
         CanonicalPrivateInheritedToolUser;
     late final Method invokeTool;
     late final Method invokeToolNoInput;
     late final Method invokeToolMultipleSections;
-    late final Method invokeToolNonCanonical, invokeToolNonCanonicalSubclass;
-    late final Method invokeToolPrivateLibrary,
-        invokeToolPrivateLibraryOriginal;
     late final Method invokeToolParentDoc, invokeToolParentDocOriginal;
     // ignore: omit_local_variable_types
     final RegExp packageInvocationIndexRegexp =
         RegExp(r'PACKAGE_INVOCATION_INDEX: (\d+)');
 
     setUpAll(() {
-      NonCanonicalToolUser = fakeLibrary.classes.named('_NonCanonicalToolUser');
-      CanonicalToolUser = fakeLibrary.classes.named('CanonicalToolUser');
-      PrivateLibraryToolUser =
-          fakeLibrary.classes.named('PrivateLibraryToolUser');
       ImplementingClassForTool =
           fakeLibrary.classes.named('ImplementingClassForTool');
       CanonicalPrivateInheritedToolUser =
           fakeLibrary.classes.named('CanonicalPrivateInheritedToolUser');
       toolUser = exLibrary.classes.named('ToolUser');
       invokeTool = toolUser.instanceMethods.named('invokeTool');
-      invokeToolNonCanonical =
-          NonCanonicalToolUser.instanceMethods.named('invokeToolNonCanonical');
-      invokeToolNonCanonicalSubclass =
-          CanonicalToolUser.instanceMethods.named('invokeToolNonCanonical');
       invokeToolNoInput = toolUser.instanceMethods.named('invokeToolNoInput');
       invokeToolMultipleSections =
           toolUser.instanceMethods.named('invokeToolMultipleSections');
-      invokeToolPrivateLibrary = PrivateLibraryToolUser.instanceMethods
-          .named('invokeToolPrivateLibrary');
-      invokeToolPrivateLibraryOriginal =
-          (invokeToolPrivateLibrary.definingEnclosingContainer as Class)
-              .instanceMethods
-              .named('invokeToolPrivateLibrary');
       invokeToolParentDoc = CanonicalPrivateInheritedToolUser.instanceMethods
           .named('invokeToolParentDoc');
       invokeToolParentDocOriginal =
@@ -587,23 +567,7 @@ void main() async {
     });
 
     group('does _not_ invoke a tool multiple times unnecessarily', () {
-      test('non-canonical subclass case', () {
-        expect(invokeToolNonCanonical.isCanonical, isFalse);
-        expect(invokeToolNonCanonicalSubclass.isCanonical, isTrue);
-        expect(
-            packageInvocationIndexRegexp
-                .firstMatch(invokeToolNonCanonical.documentation)!
-                .group(1),
-            equals(packageInvocationIndexRegexp
-                .firstMatch(invokeToolNonCanonicalSubclass.documentation)!
-                .group(1)));
-        expect(
-            invokeToolPrivateLibrary.documentation, isNot(contains('{@tool')));
-        expect(
-            invokeToolPrivateLibraryOriginal.documentation, contains('{@tool'));
-      });
-
-      test('Documentation borrowed from implementer case', () {
+      test('for documentation inherited from the implementer', () {
         expect(
             packageInvocationIndexRegexp
                 .firstMatch(invokeToolParentDoc.documentation)!
@@ -915,17 +879,18 @@ void main() async {
     test('with ambiguous reexport warnings', () {
       final warningMsg =
           '(reexport_one, reexport_two) -> reexport_two (confidence 0.000)';
-      // Unicorn class has a warning because two @canonicalFors cancel each other out.
+      // Unicorn class has a warning because two `@canonicalFor`s cancel each
+      // other out.
       expect(
           packageGraph.packageWarningCounter.hasWarning(
               AUnicornClass, PackageWarning.ambiguousReexport, warningMsg),
           isTrue);
-      // This class is ambiguous without a @canonicalFor
+      // This class is ambiguous without a `@canonicalFor`.
       expect(
           packageGraph.packageWarningCounter.hasWarning(
               YetAnotherClass, PackageWarning.ambiguousReexport, warningMsg),
           isTrue);
-      // These two classes have a @canonicalFor
+      // These two classes have a `@canonicalFor`.
       expect(
           packageGraph.packageWarningCounter.hasWarning(
               SomeClass, PackageWarning.ambiguousReexport, warningMsg),
@@ -959,7 +924,7 @@ void main() async {
     });
 
     test('with correct show/hide behavior', () {
-      expect(ADuplicateClass.definingLibrary.name, equals('shadowing_lib'));
+      expect(ADuplicateClass.library.name, equals('shadowing_lib'));
     });
   });
 
@@ -985,7 +950,6 @@ void main() async {
     });
 
     test('via reexport does not leave behind template crumbs', () {
-      expect(ClassTemplateOneLiner.isCanonical, isFalse);
       expect(
           ClassTemplateOneLiner.oneLineDoc,
           equals(
@@ -2138,8 +2102,8 @@ void main() async {
       expect(methods[1].name, equals('addAll'));
     });
 
-    test('ExtendingClass is in the right library', () {
-      expect(ExtendingClass.library.name, equals('two_exports'));
+    test('ExtendingClass is in the right canonical library', () {
+      expect(ExtendingClass.canonicalLibrary!.name, equals('two_exports'));
     });
 
     // because both the sub and super classes, though from different libraries,
@@ -2148,10 +2112,8 @@ void main() async {
         () {
       // The real implementation of BaseClass is private, but it is exported.
       expect(ExtendingClass.superChain.first.name, equals('BaseClass'));
-      expect(ExtendingClass.superChain.first.modelElement.isCanonical,
-          equals(false));
-      expect(
-          ExtendingClass.superChain.first.modelElement.isPublic, equals(false));
+      expect(ExtendingClass.superChain.first.modelElement.isCanonical, isTrue);
+      expect(ExtendingClass.superChain.first.modelElement.isPublic, isTrue);
       // And it should still show up in the publicSuperChain, because it is
       // exported.
       expect(
@@ -2801,7 +2763,7 @@ void main() async {
     });
   });
 
-  group('Extension', () {
+  group('Extensions', () {
     late final Extension arm, leg, ext, fancyList, uphill;
     late final Extension documentOnceReexportOne, documentOnceReexportTwo;
     late final Extension staticFieldExtension;
@@ -2856,7 +2818,6 @@ void main() async {
     });
 
     test('basic canonicalization for extensions', () {
-      expect(documentOnceReexportOne.isCanonical, isFalse);
       expect(
           documentOnceReexportOne.href, equals(documentOnceReexportTwo.href));
       expect(documentOnceReexportTwo.isCanonical, isTrue);
@@ -2864,8 +2825,6 @@ void main() async {
 
     test('classes know about applicableExtensions', () {
       expect(apple.potentiallyApplicableExtensionsSorted, orderedEquals([ext]));
-      expect(string.potentiallyApplicableExtensionsSorted,
-          isNot(contains(documentOnceReexportOne)));
       expect(string.potentiallyApplicableExtensionsSorted,
           contains(documentOnceReexportTwo));
       expect(baseTest.potentiallyApplicableExtensionsSorted, isEmpty);
diff --git a/test/search_index_test.dart b/test/search_index_test.dart
index 0192d5b619..23e1369f1d 100644
--- a/test/search_index_test.dart
+++ b/test/search_index_test.dart
@@ -6,6 +6,7 @@ import 'dart:convert';
 
 import 'package:dartdoc/src/generator/generator_utils.dart';
 import 'package:dartdoc/src/model/model.dart';
+import 'package:dartdoc/src/model_utils.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -50,8 +51,16 @@ class SearchIndexTest extends DartdocTestBase {
         ...library.packageGraph.libraries
             .where((l) => l.name.startsWith('dart:')),
     ];
+    // TODO(srawlins): `Library.allModelElements` is not a great fit for this
+    // test, because we can only calculate the `href` properties of canonical,
+    // documented elements. But this filter gets us approximately what we want.
+    var elements = libraries.expand((library) => library.allModelElements
+        .whereDocumentedIn(library)
+        .where((e) => e is ContainerMember
+            ? e.enclosingElement.canonicalLibrary != null
+            : e.canonicalLibrary != null));
     var text = generateSearchIndexJson(
-      libraries.expand((library) => library.allModelElements),
+      elements,
       packageOrder: actAsFlutter ? const ['flutter', 'Dart'] : const [],
       pretty: false,
     );
diff --git a/test/src/utils.dart b/test/src/utils.dart
index d84ecf6ef2..7028b0d553 100644
--- a/test/src/utils.dart
+++ b/test/src/utils.dart
@@ -380,12 +380,12 @@ extension IterableStringExtension on Iterable<String> {
 
 extension PackageExtension on Package {
   /// Gathers all extensions found across a package.
-  Iterable<Extension> get extensions =>
-      libraries.expand((library) => library.extensions.whereDocumented);
+  Iterable<Extension> get extensions => libraries.wherePublic
+      .expand((library) => library.extensions.whereDocumented);
 
   /// Gathers all functions found across a package.
-  Iterable<ModelFunction> get functions =>
-      libraries.expand((library) => library.functions.whereDocumented);
+  Iterable<ModelFunction> get functions => libraries.wherePublic
+      .expand((library) => library.functions.whereDocumented);
 }
 
 /// Extension methods just for tests.
diff --git a/testing/test_package/lib/fake.dart b/testing/test_package/lib/fake.dart
index 7b0097afc7..458cb2c3b1 100644
--- a/testing/test_package/lib/fake.dart
+++ b/testing/test_package/lib/fake.dart
@@ -1163,17 +1163,6 @@ abstract class MIEEThing<K, V> {
   void operator []=(K key, V value);
 }
 
-abstract class _NonCanonicalToolUser {
-  /// Invokes a tool without the $INPUT token or args.
-  ///
-  /// {@tool drill}
-  /// Some text in the drill that references [noInvokeTool].
-  /// {@end-tool}
-  void invokeToolNonCanonical();
-}
-
-abstract class CanonicalToolUser extends _NonCanonicalToolUser {}
-
 abstract class ImplementingClassForTool {
   /// Invokes a tool from inherited documentation via `implemented`
   ///
diff --git a/testing/test_package/lib/src/tool.dart b/testing/test_package/lib/src/tool.dart
index d08a33dd0d..e0e1e13efc 100644
--- a/testing/test_package/lib/src/tool.dart
+++ b/testing/test_package/lib/src/tool.dart
@@ -1,14 +1,5 @@
 library test_package.tool;
 
-abstract class PrivateLibraryToolUser {
-  /// Invokes a tool from a private library.
-  ///
-  /// {@tool drill}
-  /// Some text in the drill.
-  /// {@end-tool}
-  void invokeToolPrivateLibrary();
-}
-
 abstract class GenericSuperProperty<T> {}
 
 abstract class GenericSuperValue<T> extends GenericSuperProperty<T> {}
diff --git a/tool/task.dart b/tool/task.dart
index de40c21ddd..e8212ab537 100644
--- a/tool/task.dart
+++ b/tool/task.dart
@@ -913,15 +913,18 @@ Future<void> validateSdkDocs() async {
   }
   print('$foundSubLibCount index.html dart: entries in categories found');
 
-  // check for the existence of certain files/dirs
-  var libsCount =
-      _sdkDocsDir.listSync().where((fs) => fs.path.contains('dart-')).length;
-  if (!expectedTotalCounts.contains(libsCount)) {
-    throw StateError('Docs not generated for all the SDK libraries; expected '
-        '$expectedTotalCounts directories, but $libsCount directories were '
-        'generated');
-  }
-  print("Found $libsCount 'dart:' libraries");
+  // Check for the existence of certain files and directories.
+  var libraries =
+      _sdkDocsDir.listSync().where((fs) => fs.path.contains('dart-'));
+  var libraryCount = libraries.length;
+  if (!expectedTotalCounts.contains(libraryCount)) {
+    var libraryNames =
+        libraries.map((l) => "'${path.basename(l.path)}'").join(', ');
+    throw StateError('Unexpected docs generated for SDK libraries; expected '
+        '$expectedTotalCounts directories, but $libraryCount directories were '
+        'generated: $libraryNames');
+  }
+  print("Found $libraryCount 'dart:' libraries");
 
   var futureConstructorFile =
       File(path.join(_sdkDocsDir.path, 'dart-async', 'Future', 'Future.html'));