It just changed one day, no idea why. Current Mac OS and Firefox version. Attaching screen cap of sidebar on left, with too much spacing between items, and bookmarks menu on right, with proper spacing. Wondering if I accidentally hit a combo of keys one day and inadvertently changed spacing, but no idea how or why it got the way it is on the left. In some random searching for solutions, I found some that were very complex, most all Windows-based, hoping for simple, logical solution. Thanks in advance to any useful help!