Hi LiliB, most likely you will need to "mess with CSS" (nice rhyme!) unless you want to enlarge everything in Firefox by the same amount.

So to get specific, you have text on tabs, for example:

and you want the font-size larger. Regarding boldness, do you want bold on all tabs or only the "active" one?

By the way, as probably can tell, I have Windows, so if my suggestions don't end up working, it might be one of those Windows/Mac differences and hopefully we can find you a Mac users to clear it up.

Hi jscher2000, thank you for helping.

Yes, I just need the text on tabs bigger and bold on all tabs.

You can add this code to the userChrome.css file below the default @namespace line.

• https://www.userchrome.org/how-create-userchrome-css.html
• https://www.userchrome.org/what-is-userchrome-css.html

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

#tabbrowser-tabs .tab-text{
 font-size:13pt !important;
 font-weight: bold !important;
}

It is not that difficult to create userChrome.css if you have never used it.

The first step is to open the "Help -> Troubleshooting Information" page and find the button to access the profile folder.

• https://support.mozilla.org/en-US/kb/use-troubleshooting-information-page-fix-firefox

You can find this button under the "Application Basics" section as "Profile Folder -> Open Folder". If you click this button then you open the profile folder in the Mac Finder. You need to create a folder with the name chrome in this folder (name is all lowercase). In the chrome folder you need to create a text file with the name userChrome.css (name is case sensitive). On Mac you can use the TextEdit application to create and edit userChrome.css. In this userChrome.css text file you paste the text posted above.

You need to close and restart Firefox when you create or modify the userChrome.css file.