Correct. This is intentional. If your macOS offers Dark Mode, then the main UI in PM will be in dark mode. The main UI will be in dark mode as much as it possibly can be. Only the dialogs and panels will optionally run in Light Mode.
This is by design.
There is no way to override this behavior.
Hi Kirk, I've switched to dark mode for PM for a very long time now (and on my Mojave laptop I also set the OS to dark-mode), so I never noticed this. But wouldn't it be better to either
a) fully honour the OS setting for
all application windows/dialogs – despite the setting in PM's preferences –, or better yet,
b) fully honour PM's preference setting for
all application windows/dialogs – despite the OS setting –
The approach where some are (always) chosen to be dark despite the fact that the user has set things to light, feels a bit strange.