I'm using 4.3.0, on Windows 10 Anniversary Edition 64 bits.
Yes I know I need to close the settings window.
Now I remember, indeed I did modify the color in the past, and I did not think setting back the color to default would pick it automatically from Windows theme (I thought default meant the default Classic Shell color...), as it is not written anywhere (...but after thinking again, this is stupid, as there is no default Classic Shell color
), which is why I thought a "Customize the taskbar color" checkbox would be needed.
I had changed the color because I did not like it being darker than the windows' color. This is what Windows 10 does by default so Classic Shell is right for doing so anyway.
Mmh... then this thread is useless, sorry for the inconvenience, and thank you both for the help!
Maybe I can make another suggestion then: an option to make the taskbar automatically pick the Windows' color instead of the (darker) taskbar color?