The space for the filename used to be wider/longer. I used to be able to see very long filenames all at the same time.
Let's say I have a filename "Veryveryveryveryveryveryveryveryveryveryveryveryverylongfilename_001.jpg" and I want to change just the last digit to 2. I'll have to click the filename field, then scroll with the arrow buttons all the way to the last digit and then change it. This takes a lot of extra time. There are other problems also from not being able to see the whole filename (I might not even know if that last digit needs editing or not since I cannot see it). My workflow suffers from this.
Before, I used to be able to just place my cursor just beside the last digit with my mouse and then quickly do the edit.