Bookmarks no longer "drag" (Safari 18.4, Sequoia 15.4)

I just upgraded to Safari 18.4, and that did not fix what just started before then, which is that, in Edit Bookmarks, I can no longer drag a bookmark from one location to another and cannot drag a folder to another location, either. A post on this subject, but for two versions ago, had someone say what worked for them was to delete ALL of their Personal History and restarting Safari. I'm not willing to delete ALL of my Personal History yet, but I did upgrade my system, which of course involved exiting Safari, but that didn't solve the issue.