Hi Simeon, I am Paulo and I'd like to help.
There is no global setting to remove the media control overlay. It can only be disabled for each individual app.
For Spotify, you may go to click the three dots on the top left part of the app > Edit > Preferences > Display and turn off "Show desktop overlay when using media keys"
For browsers, you may check this:
https://www.elevenforum.com/t/enable-or-disable...
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