@thomasfuchs I use a Compose key on Linux (hey, this is Mastodon, you were expecting a smug Linux weenie at some point, right?).
I can easily write æ, ö, ß, λ, ⊆, д, é, è and ☭, among many other more-or-less useful things.
(and this is also part of how US-ANSI keyboards ended up becoming my favourite physical layout, with the dubious side effect that I can barely use a Danish keyboard anymore.)