Cannot add or delete items to library

[PeterD-NJ]

Since upgrading to the latest version of InDesign I am no longer able to add items to a library.  It wants me to migrate my libraries to Creative Cloud, but I would prefer these files live in the same Dropbox folder on my computer in which my .indd project files reside.

I use this feature heavily for icons and symbols used in my publication and I'd like to find a solution for this.

As you can see above, the add item and delete item icons are greyed out. Please and thank you.

[Eugene Tyson]

Try move it outside your dropbox folder as a test. 

Then try save it in the new version as a new Library file - call it Library 2026 or something. 

Then try open it in the new version and see if the behaviour is ok. 

Move back to Dropbox folder and reopen it from there - see if the issue persists.