Color configuration issue on Plasma
René J.V. Bertin
rjvbertin at gmail.com
Thu Jul 5 17:27:45 BST 2018
Have you checked under System Settings/Application Style/Window Decorations? That was at least the place to check until Plasma 5.11 .
Wherever it is now, this KCM should give you a list of window decoration "themes", each of which can have configuration options. I don't see any option that affects the titlebar colour of the Breeze window theme directly, but maybe you are not using that theme without realising it? In the list I have installed here I see a "Pastel" theme that uses a horrible (IMHO) bright blue for the entire window frame.
It's not entirely impossible either that you're seeing some effect of Ubuntu branding - though blue seems incongruent for Canonical's usual colour palette.
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