1725436 - After update to v91.0, websites look ugly, v90.0.2 is okay

Status: RESOLVED FIXED

(Firefox :: Untriaged, defect)

Description

[Christian]

Attachment: Comparison between old / new look.

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 Safari/537.36

Steps to reproduce:

In version 90.0.2, all websites looked nice. FF updated itself to v91, and all websites are really ugly and unuseable.

Went back to 90.0.2 - all was well again. Updated again: same result. Deleted all caches and cookies, started Firefox in "safe mode", have reset Firefox (started it with the Option key pressed), tried to open pages in a "private" window, changed security settings between standard and strong, etc - all with no effect.

This happened on 2 different Macs:

1. iMac (Retina 5K, 27-inch, Late 2015), Intel Core i5, 8 GB RAM, macOS 10.14.6 (Mojave).

2. MacBook Air (Retina, 13 inch, 2020), 1.1 GHz QuadCore Intel Core i5, 16 GB RAM, macOS 10.15.7 (Catalina).

Actual results:

You can see - with one example site - how a website used to look like and how it does look now with FF 91.0

On top, the site as it should appear
On bottom, the "new look" of Firefox 91.0 - really awful and unuseable

Expected results:

I want to see the website as it was displayed before, and as it is displayed by other browsers like Google Chrome, Safari and Opera.

Comment 1

[Tom S [:evilpie]]

This is caused by a new feature in Firefox 91

Firefox now automatically enables High Contrast Mode when "Increase Contrast" is checked on MacOS

https://www.mozilla.org/en-US/firefox/91.0/releasenotes/

Comment 2

[Morgan Reschenberg [:morgan]]

If you'd like to change this back, you can navigate to about:preferences > Language and Appearance > Colors > set dropdown to "never" > OK

Comment 3

[Christian]

Thank you all for the help! It worked. But one question still remains:
I threw away all settings files for Firefox (also using App Zapper), but this specific setting remained somewhere. No idea why.
-christian

Comment 4

[Mark]

This has definitely happened but setting that flag does not fix all the problems.

I have other sites where the CSS is just not recognised. I have now stuck to v90

First I do want the high contrast so turning Firefoxs option off is not a usable option

I use Tree tab Style for tabs and Stylus for altering CSS. Even with the firefox flag not set the tabs are all white and the CSS override does not work.

Comment 5

[Mark]

Also want the high contrast overides for links - but they should not break the whole page. I have sites e.g. http://forum.sealionpress.co.uk/index.php where I have chosen the dark site's CSS and it becomes ion new Firefox black on white. Without setting it is as expected - except my Stylus override of one style is not observed

Comment 6

[Mark]

Sorry the stylus issue is a profile one but the rest stands

Comment 7

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1713015

Comment 8

[Steve]

This version 91 is not very good. All background colors are gone. Text over images are in a box.

Comment 9

[liam]

The implementation of this change is really sloppy. I am sure I am one of many users who were perplexed by the rollout and even re-installed Firefox, wasting valuable time trying to figure this out when it simply could have been communicated prominently in the first place.

Comment 13

[Mark]

As this makes such a mess ie not using CSS at all on some pages and no plugiuns using CSS can be used. So you have to keep on old Firefox

Would not the best thing to do be to rollback these changes. The attempt to do whatever was intended needs to be reimplemented and only released when it works.

Comment 14

[Raffi]

In case it is useful to know, here was my experience with this feature. Some time ago, I enabled "increase contrast" in Mac OS X. I don't remember why. The change is so subtle, I'd forgotten I'd enabled it. Recently, when Firefox updated, it inferred from this operating system setting that I wanted to use the browser's default colors. The consequence was that Firefox seemed, to me, to be confused about how to render websites. I began removing my extensions, trying troubleshoot mode, and downloading other versions of the browser. I eventually filed a bug which led me here.

My two cents: Switching to the browser default colors does not make everything on a website easier to see. Instead it makes many things harder to see. After all, websites often rely on particular combinations of colors - especially border colors - to make elements distinct. If the Firefox team would like to accommodate users who want higher-contrast colors, there may be a better way of doing this.

Comment 16

[Julien Cristau [:jcristau]]

Bug 1726606 turned firefox high contrast mode back off by default for users with the macOS "increase contrast" setting, so this should be less of an issue as of 91.0.2.

Comment 17

[Pascal Chevrel:pascalc]

Fixed by backout across all channels.

Comment 18

[Mark]

Firefox nightly 94.0a1 (2021-09-08) still shows the same issue ie a non dark Tree Style Tab certain sites with no CSS.

90.0.2 (64-bit) works

Comment 19

[Mark]

Example page is http://forum.sealionpress.co.uk/index.php