Thank you, Mary, for the advice; I do apologize for the late reply, since I don't log in the forum as often as I should. My reply comes to you two years late and in the middle of COVID19! Who would have thought back then we would be at this point in time! I plan to do a better job returning to this forum; I have learned another way to manage my fonts via Administrator (superuser) privileges with my Caja desktop file manager...and it really does work! CTRL + H will bring up my hidden .local files under "share" and "fonts." The font manager app you had recommended did not work on my computer, it appeared to be corrupted after downloading it. The "superuser" management has been a lifesaver for me.
This is how my system works:
1 - Open your file manager and under "Computer" find the name of your system (usually it's your name or some name you chose when you first installed the OS).
2 - Look for the "Home" folder and select it (click). After that, select the "share" folder (it's the only folder for me as a subfolder of Home).
3 - After you open it, select "fonts." Now activate superuser (Administrator) privileges and enter your password. Press at the same time "CTRL + H" to activate all hidden files.
4 - A new window will open, allowing you to edit the folder as "superuser." Delete and manage your fonts inside this folder. Deleted fonts are erased from the system, so use with care. The "Move To Trash" command in the drop-down list will move and automatically delete any selected fonts under "superuser."