Thanks Martin. Now I know where the tracker located.
Yes, just hope have a solution on that in the near future. Regarding the window title I think just only me prefer to not having any light background on my screen else will need an click-through-able overlay to dim it.

Requests for dark tabs and headers are tracked here:
Issue 1806 – Dark theme for session tabs
Issue 1776 – Dark theme for column headers
Neither is technically possible atm, afaik.

Dark window title is possible (though you are the first one to ask for it).

Try to request making the column bar and session tab to be dark background with light foreground. If possible same to the application's title bar.

Having these in light background color feel overwhelm when working on long time.

Version: 5.15.9
Build: 10071
Interface: Commander
PC OS: Windows 10 1809