User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:92.0) Gecko/20100101 Firefox/92.0

Steps to reproduce:

Firefox recently updated UI making it less accessible for autistic people when multiple tabs with no containers are used. As I make full use of containers I did not notice until a friend of mine (also autistic) pointed out a couple of weeks ago that he was switching to another browser because a recent change in Firefox made it difficult for him to use the browser.

At first it didn't make sense to me, as I make use of containers, but when I tried to open multiple non-container tabs I would notice the issue.

Actual results:

With the current system template, there is too few visual distinctions between tabs, making it chaotic and visually disturbing for some autistic users.

Autistic people process sensory stimuli differently from neurotypicals, including, for some autistic people, visual information. Although sensory processing might vary a lot from individual to individual, it is a general guideline that visually ordered visual information, with clear distinctions between objects, is less likely to be harmful.

Depending on the autistic person and on the moment (and also depending on how long the person is browsing) this might be just very unpleasant to look at, while for others it is potentially harmful, with the risk of causing, for instance, a sensory crisis.

Expected results:

There should be a better distinction between tabs making UI less chaotic if Firefox wants to be accessible for everyone. When containers are used it seems fine (to me, at least) because the colored bar at the top of each tab, with this gap between the bars, makes each tab very distinctive from each other.

Also, when such changes in UI are made they could, ideally, go through a preview stage when both old and new are available options and there is an easy way to roll back, and the disabled community could be consulted on the changes before they are made permanent. In a certain way, this is not just a defect in Firefox, but also in the development process.

The Bugbug bot thinks this bug should belong to the 'Core::Disability Access APIs' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Asa, this looks like it might be a duplicate of bug 1704347. Does the attached image fit with that assessment?

Yep. Duplicate.

Well, I don't know the guidelines for considering something duplicate.

If it is about the firefox feature I totally agree, but if this is about the origin of the problem it seems like a completely different bug.

While the initial comment in the other bug refers to high contrast, the underlying issue here is that there is insufficient visual distinction between tabs with the new UI. This is why your bug was marked as a duplicate, as there is ongoing work associated with the other bug to try to resolve this. Thanks.