Merged r11522 from trunk (#13340).
Merged r11578 from trunk to 2.3-stable (#13414)
Bulgarian translation updated and changed by Ivan Cenov.
Bulgarian translation updated and changed by Ivan Cenov (#13414)
Backported r11494 from trunk.
Merged r11507 from trunk (#13329).
Merged r11506 from trunk (#13329).
Merged r11497 from trunk (#13329).
Merged r11488 from trunk.
Merged r11571 from trunk (#12122).
Preserve gantt options when changing filters (#12122).
