ff-90.0.2 Followed community advice but the following fails to work. https://support.mozilla.org/en-US/questions/1306797 1. open "Help -> Troubleshooting Information" & find button to access the profile folder 2. find this button under: Application Basics > Profile dir > Open directory=/home/ab2qik/.mozilla/firefox/p3bbumtq.default-release click this button to open profile folder in Explorer 3. create a dir=chrome in this folder(all lowercase) 4. In dir=chrome create a text file=userChrome.css(all case sensitive) 5. userChrome.css - paste in text below 6. paste below code into chrome/userChrome.css: @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */ #personal-bookmarks .toolbarbutton-text { font-size: 15px !important; } 7. (Quit/Exit) browser & restart Firefox when you create or modify the userChrome.css file. 8. Firefox 69 & later about:config > toolkit.legacyUserProfileCustomizations.stylesheets = true set above pref to true this enables userChrome.css & userContent.css in chrome folder

#personal-bookmarks .toolbarbutton-text { font-size: 15px !important; }

.sidebar-placesTreechildren::-moz-tree-cell-text {font-size:15px!important;}