You can modify properties like the name via the Properties item in the context menu or via the Details pane at the bottom of the right pane in the Bookmarks Manager (Library; Show All Bookmarks).

cor-el said

You can modify properties like the name via the Properties item in the context menu or via the Details pane at the bottom of the right pane in the Bookmarks Manager (Library; Show All Bookmarks).

I know that but how would I regain the rename function when right clicking?

I also tried to see if restarting FireFox with Addons disabled would fix it but I'm still missing the function in Safe mode too.

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Hi, open the 3-bar menu > Help > Troubleshooting Information, then near the bottom look for Places Database and click on Verify Integrity, then restart Firefox - Use the Troubleshooting Information page to help fix Firefox issues. If that doesn't help, you may have a corrupt places.sqlite file in your Profile. For that, and other things to check, please see - Can't add, change or save bookmarks - How to fix.

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!

Scribe said

Hi, open the 3-bar menu > Help > Troubleshooting Information, then near the bottom look for Places Database and click on Verify Integrity, then restart Firefox - Use the Troubleshooting Information page to help fix Firefox issues. If that doesn't help, you may have a corrupt places.sqlite file in your Profile. For that, and other things to check, please see - Can't add, change or save bookmarks - How to fix. If your question is resolved by this or another answer, please take a minute to let us know. Thank you!

I went and verified integrity and completely exited from Firefox, after that I restarted it and still was missing the function. So I proceeded to follow the instructions of the link you posted and still am missing the function.

I also reinstalled Firefox (didn't refresh) and the function is still missing.