When the following is called:
css({'data-css-nil': ''})
The following error is thrown:
Error: [glamor] an unexpected rule cache miss occurred. This is probably a sign of multiple glamor instances in your app. See #79
I'm not sure whether css({'data-css-nil': ''}) should be valid - but if not, perhaps the error message should be more descriptive. In Glamorous it is possible to get this error without having multiple instances of glamor.
See:
#373
paypal/glamorous#396
paypal/glamorous#397