Retrieve accent system color

[uazo]

I think it might be of interest to you. it seems that in firefox on the mac platform it is possible to obtain the colour set by the user. if it were true (I don't have a mac to verify this, but it seems to me that you do) it could be a source of fingerprint, that you could put on your list.

chromium is implementing the same functionality.

refs:

• https://bugs.chromium.org/p/chromium/issues/detail?id=1338061
• https://chromestatus.com/feature/5068127364186112
• https://bugs.chromium.org/p/chromium/issues/detail?id=1425116