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It is disappointing to hear reference to switching operating system theme. I don't have to monkey with my operating system when I use the dark theme in IntelliJ or GitKraken. Why does SmartGit have this unique requirement compared to its competitors?
Customer support service by UserEcho
On Ubuntu 16.04, I found that some dark themes aren't recognized by smartgit (Adwaita, Vivacious-dark-*). I ended up going with Arc-dark-solid, and also confirmed that Vivacious-zblackout-* works.