You can do that with a file called userChrome.css. I can post the code I have used for many years if you want to take that route. (Note: remove blank space in link below.)

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

Note that you can also shorten bookmark names by editing the bookmark via the right-click context menu or in the Library.

• https://support.mozilla.org/en-US/kb/bookmarks-firefox

Thanks, terry21. I would love to know how to this on the css file. Thanks for any further info!

OK, this has worked for years. I have a note of this link. https://support.mozilla.org/en-US/questions/1353930#answer-1450978

toolbarbutton.bookmark-item > .toolbarbutton-icon {
  display: none !important; }