And most mainstream GUI toolkits are, as well. It can be said that UTF-16 is the de-facto standard in-memory representation of unicode strings, even though some runtimes (Rust) prefer UTF-8.
Why are you guys talking like there were dozens of GUI toolkits in mainstream use? It's basically web stuff, Qt, and then everything else. Web would be UTF-16 as discussed above, Qt is UTF-16, and even if we entertain the admittedly "large just behind-the-scenes" Java/.NET market, that's also all UTF-16. WxWidgets being a fence sitter can do both UTF-8 and UTF-16, depending on the platform.
Which players am I missing? GTK and ImGUI? I don't think they are too big a slices of this pie, certainly not big enough to invalidate the claim.
No. Windows use UTF-16 internally. Most GUI toolkits do not.
> It can be said that UTF-16 is the de-facto standard in-memory representation of unicode strings, even though some runtimes (Rust) prefer UTF-8.
No, that wouldn't be true at all.
Your technical merit seem to be limited by your Windows experience, and even that is dated.
Microsoft recommends UTF-8 over UTF-16 since 2019 [1].
1: https://learn.microsoft.com/en-us/windows/apps/design/global...