Bug 996186 - Customize mode briefly makes titlebar transparent during transition. r=Gijs, a=sylvestre

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extra : transplant_source : %96l%5EY0FdH%7BG%7D%E6%E2%DE%FF%F5%CF%813%40
Bug 987792 - increase panel buttons' labels' clip rect height, r=jaws, a=sylvestre

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extra : transplant_source : cd%06%91%3B/%A3tj%3C%AEo%07%ED%1E%EEf%84%04Q