Sluggish behaviour: dragging items onto tags

cream_dream

I am adding color-coded tags to items in my library by dragging the item onto the desired tag. Zotero is doing this sluggishly. I have to hold each item above the tag for about five seconds before the software highlights the tag to allow it to be added. Once that tag is added, the same delay occurs if I want to add another tag to the same item. By contrast, adding tags from the "Tags" tab on each item is perfectly responsive.

I am using Windows 10.

Edit: after reading other threads, I tried disabling and then re-enabling the "Better Bibtex for Zotero" addon in Zotero. This fixed the problem.