User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0

Steps to reproduce:

1. Tried to create a new folder in the bookmarks library (Ctrl+Shift+B to access).
2. Tried to move new bookmarks into that folder

Actual results:

1. Creating a new folder in the bookmarks library is not working, it is working when you do it in the bookmarks bar, but bugs out when you do it in the library.

2. And if you try to move a bookmark to another location or even shift it a few bookmarks over, it's not working. They have become locked in their positions.

Restarting Firefox didn't change anything either.

Expected results:

1. New folder should have been created in the bookmarks library.

2. New/any bookmarks should have been able to move to new positions or into a folder in the bookmards library.

Please could try running an integrity check:

• Go to the three-bar menu -> Help -> Troubleshooting Information
• Scroll down the page to find the "Places Database" section (it is near the bottom).
• Click the "Verify Integrity" button, this may take a few seconds to run.
• Then restart Firefox and see if your issues still occur.

(In reply to MozillaDude from comment #0)

2. And if you try to move a bookmark to another location or even shift it a few bookmarks over, it's not working. They have become locked in their positions.

This part is probably bug 1557853. Running the integrity check and restarting should help workaround that.

Yeah it's fixed. I can now both add, move, delete bookmarks & create new folders in library.
Thank You mark. Please mark this fixed.

Thanks for letting us know. I'll mark this as a duplicate of bug 1557853, since that is the one likely to have caused this.