unicode-fonts

For a ~50-year-old program, Emacs’s support for multilingual input — and really, it’s all-round flexibility — continually amazes me! For myself I prefer my own custom keyboard layout [0], because it works outside Emacs too, but I’d happily use Emacs’s own input methods if that would be sufficient. (In fairness, I have found one weak spot, namely font support… I’ve used ‘unicode-fonts’ [1] with some success, but reportedly it doesn’t work with the latest Emacs. Ah well, it’s at least fairly rare that this becomes a problem in practice.) [0] https://github.com/bradrn/Conkey [1] https://github.com/rolandwalker/unicode-fonts

Regarding your long lines issue - from your description it sounds instead like an unicode issue which I also ran into a while back. What happens is that your main programming font does not have the unicode characters, so Emacs falls back to searching all your fonts for each character it can't find, which is slow if it has to search through many different fonts. The solution is to ensure you have symbol fonts installed - see the list of fonts here: https://github.com/rolandwalker/unicode-fonts

See also: https://github.com/rolandwalker/unicode-fonts (a different direction, starts from removing Unifont)