Force dark-mode independently of system settings.

[Sneakpeakcss]

Expected behavior of the wanted feature

_{Surprisingly, this was never properly requested and only lived as now-closed questions scattered across different repos.}

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Given that the cplugin based menu implemented in the #5500 (comment) is also controlled by dark mode, we now have other UI elements affected by this, and there may be more in the future. It is time to add options to control the behavior of mpv's dark mode.

Originally posted by @dyphire in #11473 (comment)

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The above seems to be exhaustive.

Alternative behavior of the wanted feature

No response

Log File

No response

Sample Files

No response