When using mobile (although not mobile emulation mode on devtools) there is a flash of blue when tapping a button even if that's not set anywhere.
By default mobile browsers add blue highlights on taps to give feedback before the next page loads, but we already provide instant feedback by darkening/rippling and the default browser UI is redundant.
I suspect we simply haven't done much testing on mobile and didn't notice we need to set -webkit-tap-highlight-color to transparent.
When using mobile (although not mobile emulation mode on devtools) there is a flash of blue when tapping a button even if that's not set anywhere.
By default mobile browsers add blue highlights on taps to give feedback before the next page loads, but we already provide instant feedback by darkening/rippling and the default browser UI is redundant.
I suspect we simply haven't done much testing on mobile and didn't notice we need to set -webkit-tap-highlight-color to transparent.