Hi Mathias,
first of all, thanks for great application - I use it at home and also recommend to colleagues who I know are using dual panel managers.
I have a small feature request - currently there is only 1 history button for whole program. It can be invoked via alt+down, but it mixes up the folders from both panels. At work I use FC, as it is approved for internal use (I work in multinational so I cannot just install what I want - lots of rules to follow....). Anyway - in FC there are separate history buttons for each panel, which for me at least is more user friendly.
It could be left from the "show/hide folder tree" button or in the same area, and clicking the button or hitting alt+down would show the history list from that specific panel. Currently when I'm in the right panel, clicking alt+down opens the menu on the upper left side, which takes away focus from the panel...
I know there is per-panel history available when you hold down the "back" button - still there is only 1 button in upper left corner and is not easily accessible by keyboard (must grab mouse and to allthe way to upper left....)
Probably the same could be done with bookmarks/favorites button.
Thank you for consideration