Match highlighting doesn't work correctly with Japanese, etc.

[slevithan]

The reason is match/subpattern highlighting expects every character to take the same width due to the use of a monospace font. However, the width of e.g. English characters doesn't apply to e.g. Japanese characters.

Example: try using /./ to match "片仮名" or "カタカナ".

There's probably some way to determine the actual width of matched text as rendered on the screen, which would be a part of fixing this.

[slevithan]

The library https://github.com/sindresorhus/string-width offers an alternative approach that might be helpful with this.