Win11, Laz. 4.6, default light theme.
I find it mostly to be a bit hard to identify the active tab within the IDE Code Editor ("oh, which one of the tabs is the active one .... <search> ...").
Yes, i'd assume the underlying control might be OS based, but maybe i simply did not see yet a if there are related options.
I won't even expect the bg colors could be changed ... but maybe a different font color for the active tab's caption, or font bold?