The element web cannot download the files if authentication is enabled.

[nickolay168]

Steps to reproduce

First of all thank you for the element-web. It is a great way to serve Matrix!
I have found the issue in the element web, preventing file exchange.

1. Where are you starting? What can you see?
   Setup: The element was installed on ubuntu machine from the deb package and was served as a static page from /var/www/html/element. In the config.json it was pointed to the matrix web server.

2. What do you click?
   Upload any file to the matrix server. If it will be an image, the preview will not be shown. The download will result in 404 error as follows:
   An error occurred while downloading this file
   DownloadError: MatrixError: [404] Not found (https://matrix.example.com/_matrix/media/v3/download/xxxxx/xxxxxxxxxxxxxxxxxxxxxx?allow_redirect=true)

3. More steps…
   The problem happens, because the client tries to access files without authorization as it was before implementation of 3916 proposal.
   There is a logic in element-web, which should handle this issue, however, it does not seems to work on web-client side.

I also have confirmed that matrix server can handle the requests properly:

# Results in 404 error
curl -G https://matrix.example.com/_matrix/media/v3/download/xxxxx/xxxxxxxxxxxxxxxxxxxxxx
# Will download encrypted file
curl -H "Authorization: Bearer yyyyyyyyyy" -G https://matrix.example.com/_matrix/media/v3/download/xxxxx/xxxxxxxxxxxxxxxxxxxxxx

It would be great to have the logic adding authenticating the request on the client side.

Outcome

What did you expect?

What happened instead?

Operating system

No response

Browser information

No response

URL for webapp

No response

Application version

No response

Homeserver

No response

Will you send logs?

Yes

[MidhunSureshR]

Most likely your browser does not support service worker or it is failing: https://firefox-source-docs.mozilla.org/devtools-user/application/service_workers/index.html#debugging-your-service-worker.

But this issue needs more info:

• You installed a deb package so are you having this issue on element-desktop?
• If this is actually on element-web, what browser are you using?
• Your curl request is using the old endpoint deprecated by MSC3916, so does the homeserver have authenticated_media turned on?

[nickolay168]

Thank you for your response!

• I have install the deb package of element-web on server, so that it was served as a static page.
• I have tested element-web on firefox 138.0.1
• The curl request, using deprecated endpoint results in 404 error, which is expected, while the request with bearer token to the new endpoint succeeds. The check on service worker also should result in replacement of a deprecated endpoint (I have confirmed that _matrix/client/versions path contains v1.11) by the new one, however I do not see the running service worker, so, probably it is the issue.

[t3chguy]

Will you send logs?
Yes

Not seeing any logs from you

[Echsecutor]

possibly related:

We are using element web and it does not display images any more. This is a direct consequence of upgrading to Element version: 1.11.100, the issue did definetly not ocure in 1.11.97.

Instead of any image that is sent after the upgrade or was send before the upgrade, the new web ui displays a, error downloading image

We are running a synapse 1.129.0 (simultaneously upgraded with the UI, but still serving images to other clients)

[nickolay168]

Will you send logs?
Yes

Not seeing any logs from you

Sure, I can provide the logs, however server side is not informative.

2025-04-22 05:33:48,755 - synapse.access.http.8008 - 508 - INFO - GET-12 - [ip_address] - 8008 - {None} Proce
ssed request: 0.005sec/0.001sec (0.000sec, 0.000sec) (0.001sec/0.003sec/1) 45B 404 "GET /_matrix/media/v3/thumb
nail/xxxxxxxxxxx/yyyyyyyyyyyyyyyyy?width=14&height=14&method=crop&allow_redirect=true HTTP/1.1" "[My useragent string]" [0 dbevts]

This is just a standard response sent in case if there is an attempt to get file by the legacy path.
All the attempts to get files as https://matrix.example.com/_matrix/media/v3/download/xxxxx/xxxxxxxxxxxxxxxxxxxxxx will return 404 unless the file was uploaded before the MSC3916 was implemented.

Which logs could help investigation?

[nickolay168]

possibly related:

We are using element web and it does not display images any more. This is a direct consequence of upgrading to Element version: 1.11.100, the issue did definetly not ocure in 1.11.97.

Instead of any image that is sent after the upgrade or was send before the upgrade, the new web ui displays a, error downloading image

We are running a synapse 1.129.0 (simultaneously upgraded with the UI, but still serving images to other clients)

It certainly could be. Are you getting 404 error while trying to download file marked as "Error downloading image"? I am also under impression that it used to work, however I have tested it on somebody else server.

[Echsecutor]

Sorry, I think, eventually, our issue was not related to this one. After some investigation we fixed a broken routing outgoing from our synapse server to the interne, restarted everything, and now the web client is correctly serving the images again. It might even have been a

Did you try turning it off and on again?

issue in our case. ;)

[t3chguy]

Sure, I can provide the logs, however server side is not informative.

Client logs are what the Yes was answered in regards to

[mprt]

I've just sent some logs from my element-web session.
please see event ID $Wi_vdnDbeCRlfrPW2_tnZeLT5hCIQvXPg_bVZdHtdfY or $1649WMqWkJJQY7eHPFxD7If54hYRGmjEWAyxfRVZilw as an example of image messages that show the error message.

[nickolay168]

I have looked over journals... It contains a lot of private information, however there is no ServiceWorker or SW tags in it, assuming that service worker did not started. Could I provide some specific parts of the jogs?

I also do not see the serviceWorker in the application. The error in the console says

Error: URL constructor:  is not a valid URL.
Stack in the worker:resolveSourceMapURL@resource://devtools/client/shared/source-map-loader/utils/fetchSourceMap.js:56:22
getOriginalURLs@resource://devtools/client/shared/source-map-loader/source-map.js:73:24
workerHandler/</<@resource://devtools/client/shared/worker-utils.js:115:52
workerHandler/<@resource://devtools/client/shared/worker-utils.js:113:13

Resource URL: wasm:https://matrix.example.com/element/bundles/667479c8bcd11a3fb5b2/bundle.js%20line%202%20%3E%20WebAssembly.instantiate
Code map URL: null