Moving the indicator inside the tab content isn't going to solve the issue for all themes. A better solution might be to allow custom colors configurable by the user ([bug 1325057](https://bugzilla.mozilla.org/show_bug.cgi?id=1325057)) and/or through the Theming API. BelFox: Do you mind closing this issue in favor of the bug I mentioned above?
Bug 1703029 Comment 3 Edit History
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Moving the indicator inside the tab content isn't going to solve the issue for all themes. A better solution might be to allow custom colors configurable by the user ([bug 1325057](https://bugzilla.mozilla.org/show_bug.cgi?id=1325057)) and/or through the Theming API.