Auto User Interface / Appearance in Photoshop and illustrator

the commenters above seem to not understand what photoshop actually is. first of all 'working with color' is pretty a subjective theme, if your goal is creative and you don't have to follow rigid schemes comfort might be the most important thing. secondly, the other way around, i might need the program to just edit the size of a file (happens constantly to me withmostly  an external workflow) or some other smaller edit: i don't need an 'accurate' environment for that, on the other hand it's annoying to have to spend more time to set the theme than for the edit itself (or just having to bear it)

If such a feature existed, it would be the very first thing I would disable. The most important requirement for a digital darkroom is to maintain a stable environment, and the application interface is a crucial part of it.

And in fact, to make any sense as compensation, it should be dark at day and light at night. Not the other way round.

The default dark interface is bad enough in itself. It deprives your perception of a clear visual reference to judge tonal relationships. In effect, it makes everything look good, muddy highlights and all. I want the grim truth, not a pretty picture.

You can change the Photoshop color theme appearance under the Interface tab in Photoshop preferences (but the colour is fixed).

Post feature requests here: https://feedback.photoshop.com

Personally, I think such a feature would be inappropriate for a colour managed workflow.