Hi, unfortunately, no, Firefox uses your system font for the user interface font.

There is an unofficial, unsupported workaround that involves creating a userChrome.css file. However, as a Windows person, I don't have the ability to test out rules for MacOS. You could consider asking on this subreddit where CSS wizards hang out:

https://www.reddit.com/r/FirefoxCSS/

Thanks for your reply. Given the same system (MacBook Pro) fonts and size, browser Chrome's bookmarks fonts and size appear to be smaller and comfortable. However, the problem with Chrome and Safari is that they keep on issuing "Not Private" error when loading many websites, for example rumble.com, and infection2020.com and etc. I've just discovered that Firefox extended release 78 has no issue to load any of those sites. But bookmark fonts and size are minor issues that I can live with.

Thanks for your reply. Given the same system (MacBook Pro) fonts and size, browser Chrome's bookmarks fonts and size appear to be smaller and comfortable. However, the problem with Chrome and Safari is that they keep on issuing "Not Private" error when loading many websites, for example rumble.com, and infection2020.com and etc. I've just discovered that Firefox extended release 78 has no issue to load any of those sites. But bookmark fonts and size are minor issues that I can live with.

I should ask, is the overall user interface too large? There is a global scaling factor in Firefox that adjusts the size of everything in the browser, as if you zoomed the enter application in or out. But that also affects button sizes, so if you wouldn't want those to be smaller, this might not be worth testing.

Global Scaling Factor

The following setting governs both the content area and the "chrome" area (menus, toolbars, and tabs). You can adjust the value, but it might be hard to find just the right number:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

More info/warning on the Advanced Configuration Editor: Configuration Editor for Firefox

(2) In the filter box, type or paste devp and pause while the list is filtered

(3)You can edit the value of layout.css.devPixelsPerPx but the relevant numbers are different for regular displays and Retina displays:

• Regular display: 1.0 = 100% => 96 dots per inch
• Retina display: 2.0 = 100% => 96 dots per inch

Note that -1 or -1.0 is a special flag that indicates to follow the system setting.

If setting the value to 100% is too large, you can try 0.9 or 1.8 (regular or Retina); if setting the value to 100% is too small, you can try 1.1 or 2.2 (regular or Retina). Et cetera.

Please be very careful not to enter extremely large or small values because that is difficult to recover from without going out to Finder and doing a little file surgery. However, if you can still see the Reset button at the right end of the row (looks like a back arrow with an arch to it), you can use that to restore the original value and start customizing again.

Note that Firefox 78.15.0 is the last version for your Mac OS X platform (mozilla-mac-eol-esr1), so you will no longer receive updates.

• https://support.mozilla.org/en-US/kb/firefox-mac-osx-users-esr

Hi jscher2000,

Thanks for the devp setting tips, I've tweaked the setting a bit, but it did not change the bookmark fount size by much.

For your reference, I have attached two images in comparison. The first image with smaller fonts is from Chrome bookmark pull down menu, the other one with bullky looking fonts are from Firefox Extended Release. I suspect this has been the case since day one.

Hmm, I don't know why your bookmark folder drop-down uses a different font from the bookmarks toolbar. From a Windows perspective, they should match. Is the font on that drop-down the same one used for the main menu bar drop-downs (Firefox, Bookmarks, etc.)? I feel like there must be some explanation...

Hi Jscher, You've raised a good point, which I didn't pay attention. The fonts from Firefox main menu bar and the bookmarks drop down menus are almost identical. Please see the image attached for detail.

I've double checked that fonts from the Main menu bar of Chrome on the same machine look identical to the fonts in Firefox. I am guessing that is from the system fonts for both browsers.

Fonts of Chrome's bookmark menus are exactly the same as the fonts from the bookmark drop down list Perhaps, it is a bug in Firefox !?

I am a Windows person who only uses MacBook Pro for traveling in the past. Thanks.

Found a 11-year-old post /thread, asking the same question ( that I have here ) how to reduce the fonts from bookmarks drop down menus in Firefox on Mac. There is a solution provided by user dickvl.

But since their navigation path is valid back then, Does anyone know how to locate the following in Fireforx Help menu? Thanks.

dickvl's solutions: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ You can set them independently for the toolbar and the drop down list if you want.

Code: Select all

   #personal-bookmarks toolbarbutton.bookmark-item {font-size:12px!important}
   #personal-bookmarks menuitem.bookmark-item {font-size:12px!important}

Add code to userChrome.css below the @namespace line. @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */ See http://kb.mozillazine.org/Editing_configuration#How_to_edit_configuration_files ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ http://forums.mozillazine.org/viewtopic.php?f=38&t=1917509

It's not part of a menu. userChrome.css is an external / unofficial / community-supported workaround. I have a website with more background information here: https://www.userchrome.org/