Adjust the look of colon when used as hour/minute delimiter
The HIG suggests using ratio (U+2236) as the separator for time, as that's how the typography is meant to look. However this has technical implications on RTL languages.
I guess the best approach would be to keep on using colon, but have Cantarell do a contextual GSUB on digit followed by colon, followed by digit rather than special casing RTL case in every toolkit/app.
/cc @mclasen to hear his opinion from the toolkit point of view.
Edited by Jakub Steiner