On: Zed: lightning-fast, collaborative code editor written in Rust (Atom team)

[wongarsu]

Probably the same as every other (good) UI library, by implementing each platform's accessibility API.

There is AccessKit [1] that tries to create a cross-platform API to make this less tedious, but I'm not sure how far along that effort is.

1: https://github.com/AccessKit/accesskit