[FIREFOX 58] - some @media rules get ignored [but work fine Firefox 57 and 59]

[Aris-t2]

Firefox 58 (release, beta, Nightly) ignores code as shown in this example

@media (-moz-os-version: windows-win7) {
  toolbar {
    background: red !important;
  }
}

@media (-moz-os-version: windows-win10) {
  toolbar {
    background: blue !important;
  }
}

Some of this projects features rely on correct OS or theme detection resulting in not applying any code part of these @media rules when loaded through userChrome.css/userContent.css.

• @media (-moz-os-version: windows-win7)
• @media (-moz-os-version: windows-win8)
• @media (-moz-os-version: windows-win10)
• @media (-moz-windows-classic)
• @media (-moz-windows-default-theme)
• @media (-moz-windows-theme:aero)

A filed bug report can be found here: https://bugzilla.mozilla.org/show_bug.cgi?id=1431933

I can confirm the issue is not present in Firefox 59 beta. I suggest to skip Firefox 58 and directly go to 59 beta 3+, if you are affected by this issue.

This bug might not get fixed, because a developers answer to another "userChrome" issue was

We won't fix issues that only occur when using a userChrome.css change.

https://bugzilla.mozilla.org/show_bug.cgi?id=1400542#c1

---

EDIT
This projects version 1.5.8 contains additional fixed files for Firefox 58. They have to be enabled manually depending on the options used.

---

EDIT (2018-03-08)
After Firefox 59 release this project will drop support for Firefox 58 (57 should still work fine, but why use it?).

[MarkRH]

Interesting. I am on 58 now and using v1.5.0 of your files and everything appears the same as it did with 57 (Windows 7 Pro with Classic skin). I'll probably leave it as is. Anyway, thanks for your work. My current config is here: http://www.markheadrick.com/firefox/firefox_config.php#appearance

[Aris-t2]

Only some features broke or cause glitches.

Windows Classic Theme

• classic bookmarks button popups background color
• appbutton in titlebar + maximized mode
• tabs below navigation toolbar > background/border colors
• context menu labels position
• icons+text / text modes > button appearance

Windows 10

• squared tabs > caption buttons
• tabs below navigation toolbar > top toolbar position

[Speravir]

Do I understand this right that now after publication of version 59 all these fixes can safely be disabled? And could also be removed from new releases?

[Aris-t2]

Yes, all Fx58 fixes are not required by Fx59+.
I will remove them soon.

[Aris-t2]

@mazesy
A Firefox bug in version 58 broke usage of some @media rules. Mozilla refused to fix this problem and I have added these fixes as a temporal workaround to the project. Future CustomCSSfoxFx "versions" will stop supporting Firefox 58, Fx57 and 59+ will work fine. There is no valid reason to stick with Fx 58 after 59 release.

[ghost]

@Aris-t2 , OK. I admire your commitment moreover with perpetual Firefox internal modifications. I also really -- I mean, really -- appreciate your work, I use it extensively.

Concerning what I had above mentioned concerning a setting which would no longer work with FF59, it didn't include @media rules (your answer did though), I've found an old CSS line I used with Stylish with previous to 57 Firefox versions. It's basically basic but does the job, mine anyhow as I was aiming to change only nav-bar and PersonalToolbar background colors ...

/* background color on toolbars */
#navigator-toolbox > #nav-bar, #navigator-toolbox > #PersonalToolbar {background: #E8E8FF !important;}

That's all I wanted. For the rest I rely on CustomCSSforFx

[Aris-t2]

If you are using this projects full release, you can configure everything inside /config/ folders files incl. toolbar colors (see color_variables.css). Your code most likely is not able to override default code set by this project. Make sure you are using the latest version (1.7.6).

[Aris-t2]

Firefox 57/58 support dropped with the releases of 1.7.7 and 1.7.8.