Can't resize Query panel

There's a strange bug where sometimes I'm not able to adjust the size of the Query panel, only the results panel, but when resizing the results panel the Query panel never gets larger.

The thing is, this only happens ~25% of the time and I haven't been able to figure out what causes it. No clue when it will or won't happen and why. I'll try to add more info here when I see it, but for now all I can offer is that it happens infrequently but consistently, and without any noticeable cause.

This was already reported in another thread.