HighContrast: Improve contrast of notebook tabs (GTK 3.24)
This is a cherry-pick of !877 (merged) for GTK 3.24. See !877 (merged) for details, but basically it makes notebook tabs more readable on the High Contrast themes.
This is a cherry-pick of !877 (merged) for GTK 3.24. See !877 (merged) for details, but basically it makes notebook tabs more readable on the High Contrast themes.