In the Tag Sources, Search Results, for no specific reason or file, horizontal scrolling randomly stops working. The horizontal scroll bar doesn't show and the right and left keyboard arrows won't scroll sideways either.
There is data to scroll to because when I make the title fields very small, the other fields do show up (this only works when the second title field is in the non-scrollable window.) The fields don't remain sized after a sort either but when scrolling is working that's not an issue.
Vertical scroll still works on both mouse and keyboard.
The trackpad solution doesn't work on my desktop Mac because there is no trackpad. Also there is no Appearance under Settings in either the app or on my Mac so I can't turn on Show scroll bars.
This happened when I was using the trial version and it's happening again now with the paid version. I can come back later to use the app again and it will sometimes be working again. Just restarting the app doesn't make the scroll bars come back on (nor the arrow keys work) but then after some random uses/restarts scrolling works again for a while. Can't reliably reproduce the error but if I use the app long enough then horizontal scrolling will stop working.