Mentioned non-English user names do not get linked

[fduraibi]

When you mention someone with @ sign their user name gets a hyperlink which will open a quick user profile on the side bar. However, if that user name was in written in characters other than the default (English alphabets) then it won't get the link. (see the picture)

• That user name was picked up from the suggested list.

[fduraibi]

I think this #1566 will solve this issue.

Since the problem is that javascript native regex doesn't support unicode characters and they need to be converted to codes to work.

[fduraibi]

Fixed in #1639