An interesting bug/feature.
Launch PB. Now if you create a thought by producing a link through a gate
leave a dialog open and switch to another window. Everything will be as should be. But when you try to bring PB back, you'll get back only the dialog. You'll have to close it to get the main window back.
If you try that again (second, third, etc. times after launching the PB) you'll get "always on top" dialog window:
The most interesting thing is that sometimes F6-F8 keys works as it should be, without "always on top" effect. Sometimes not. And after I've played a little with the dialog windows I managed to make the main PB window "always on top". Unfortunately I haven't figured out how to replicate the effect.
PB 184.108.40.206-b, Windows 7