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Firefox not taking input from userChrome.css

  • 4 replies
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  • Last reply by cor-el

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My tab bar is way, way too small on Linux. I followed Arch's own documentation on how to fix this by increasing `layout.css.devPixelsPerPx` (mine is at 1.4), and then adjusting font size by editing userChrome.css to select the desired size. Problem is that Firefox won't actually change anything based on what I put in that file. I have set `toolkit.legacyUserProfileCustomizations.stylesheets` to True, and I have attached a photo of my userChrome.css (yes, I'm using nano because Vim is too advanced for my smooth brain). I changed it to a ton of different values and I can confirm that the font size is not actually changing.

My tab bar is way, way too small on Linux. I followed [https://wiki.archlinux.org/title/HiDPI#Firefox Arch's own documentation] on how to fix this by increasing `layout.css.devPixelsPerPx` (mine is at 1.4), and then adjusting font size by editing userChrome.css to select the desired size. Problem is that Firefox won't actually change anything based on what I put in that file. I have set `toolkit.legacyUserProfileCustomizations.stylesheets` to True, and I have attached a photo of my userChrome.css (yes, I'm using nano because Vim is too advanced for my smooth brain). I changed it to a ton of different values and I can confirm that the font size is not actually changing.
Attached screenshots

Chosen solution

Ha ! I missed in your screenshot that you were using https:// for the @namespace line. This should be http:// to make this work.

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */
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All Replies (4)

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The tabbrowser-tabs container has an id and not a class name: #tabbrowser-tabs An individual tab has a class name that can be used as a selector: .tabbrowser-tab

So you can use either one of these (72px would blow the tabs, so make sure to reduce that value):

/* font size for all tab */
#tabbrowser-tabs {
 font-size: 15pt !important;
}

/* font size for an individual tab */
.tabbrowser-tab {
 font-size: 15pt !important;
}

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Thanks for the response. Unfortunately this still doesn't work. 72px was a test value to confirm that nothing was actually changing, the value I am actually trying to use is 15px so I changed that

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Fixed it - the "@namespace url" line at the top of the file was causing it to not work, so if you run into this question in the future with the same problem as me, delete that line.

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Chosen Solution

Ha ! I missed in your screenshot that you were using https:// for the @namespace line. This should be http:// to make this work.

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */