Automatic theme switch

[2-5]

It would be nice to have a System theme, which automatically picks Light or Dark depending on the active Windows Light/Dark theme.

It could read the system theme once on app start and select accordingly. With a bit more work it could automatically switch when Windows switches too.

[GitHubRulesOK]

I think that would be a very poor idea and unwanted by the majority since as you commented in other question when acidentally done is annoying but if every document was discoloured we would get more complaints.
There is NO REAL theming with PDF simply alternate USER choice of displaced colour range.

[2-5]

I meant theming the app itself, not the PDF content.

Basically automatically choosing between Settings/Theme/Light or Settings/Theme/Dark based on the current Windows setting.

I am using an automatic Light/Dark system theme changer based on the hour (https://github.com/AutoDarkMode/Windows-Auto-Night-Mode), and when it switches between Light/Dark many apps do that too if you set them to follow the system theme.

[GitHubRulesOK]

I use Automatic Night Mode it works perfectly everything is light but dimmer at night and I have plenty of other annoying dark apps. adding such code in NOT as simple as flip the night switch.

Leaving open as a request but unless you can code such ability to not disturb status quo will perhaps be a long time coming.