Issues with checkboxes can happen if you have set "browser.proton.enabled = false" on the about:config page to disable Proton.

In Firefox 91+ you can no longer disable Proton and revert changes that come with this design via "browser.proton.enabled = false" on the about:config page. Best in Firefox 91 is to set browser.proton.enabled at its default value true as the false setting can cause issues with checkboxes.

In Firefox 91+ you need to use code in userChrome.css to override changes coming with the Proton design.

• https://www.userchrome.org/what-is-userchrome-css.html
• https://www.userchrome.org/firefox-89-styling-proton-ui.html

Thanks!

Worked!

"In Firefox 91+ you need to use code in userChrome.css to override changes coming with the Proton design."

I have the same problem, missing the checkmark in checkboxes. Yes, I have proton disabled because of a big lack of usability. Proton does not match current Windows 10 design. Mozilla provides a setting to switch proton on or off and NONE is usable. On: missing color in title bar. Off: Missing check mark in check boxes.

Shaking head. Sorry, I don't understand FF developers anymore. Yes I KNOW and understand the basic points of free software. But their attitude is more than ridiculous. Cruising in their spaceship far away from earth. No ground contact any more. This arrogance is unbelievable. Maybe this post does not match community rules. Whatever. My frustration level is approximating 100.00 percent.

CSS CODING IS NOT AN ACCEPTABLE SOLUTION. Can anyone tell them?

The issue with the checkboxes is likely caused by code cleanup of pre-proton code that is midway in Firefox 91 that breaks the CSS code for the checkbox with proton being disabled. In Firefox 92 disabling Proton this way no longer breaks the checkbox, but it is likely that even less thing can be restored to previous behavior. It is either use CSS code in userChrome.css or accept the changes. At least Firefox gives you this choice where with other browser you have to accept all changes.

Good point. Well, you are right, at least there is a workaround ( ... not suitable for average FF users).

One more question: Checkmarks in preferences are missing because of "proton = false". Right then, why do I see checkmarks in all other websites, e.g. mediawiki, e-banking, online book shops ...... ?

I assume that in 91 there is only @media (-moz-proton){} code and not @media not (-moz-proton){} to be used when proton is disabled or CSS code without @media that would be used when Proton is enabled by default and all support for browser.proton.enabled has been removed. Such CSS code for the checkbox would only be used for the user interface as that is what is restyled with Proton.

Owww ... see, that's what I meant with "average user" (SCNR)

Conclusion, the "proton" setting is halfway being removed, should always be "true" and inconsistencies in the UI have to be accepted. Well, be it. Thanks anyway.

CSS CODING IS NOT AN ACCEPTABLE SOLUTION. Can anyone tell them?

Hi Semilynx, For clarification, this script is not provided by Mozilla and is not officially supported. Creating a userChrome.css file and other ways of customizing Firefox that are not exposed in the interface are there for developers, not end-users. If it were intended for end-users, you would see a menu option or checkbox; you wouldn't have to hack a text file in a hidden location.

What this means is that even though the functionality you want is no longer supported, a third-party has found a way to do it using the CSS file. If it breaks in new versions, you will need to contact the person who provided the script.

Just downgraded to FF 88.0.1 - yes I know: not recommended bla bla ... sorry guys; all UI changes since then are completely inacceptable. Come on @all users: Do the downgrade. Then uninstall the newer version. They will ask you for feedback ... maybe then they'll learn they're wrong.

Warning: Installing a previous version doesn't fix most problems

Problems with an update are generally not caused by the new version of Firefox, but rather the update process. Installing a previous version will not help in most cases. The best option is to start a new thread about your issues, where others can suggest specific solutions.

Using old versions of Firefox also poses a significant security risk.

[Warning added by moderator.]

Editing a users comment is highly disrespectful.

As the current FF version is unusable, users have exactly two possibilities: 1. Downgrade to a previous version. 2. Go away.

Treating your members as idiots will slightly move them to solution 2.

Thanks, this fixed it.

Yet another reason to hate Proton. Thumbs down to the devs who decided to stop letting those of us who loathe proton turn it off.