macOS: builtin Korean IME's hanja candidate window cannot be opened

[umajho]

Description

On macOS, while using the builtin 2-Set Korean IME, the user normally can open the hanja candidate window with Option+Return.
The section “Convert Hangul to Hanja” of this User Guide by Apple illustrates this.

Expected behavior:

Actual Behavior:

(NOTE: I typed “ㅎ” and Backspace first before typing the actual word to workaround #3095.)

➜  winit-ime-on-windows git:(master) ✗ cargo run --release
    Finished `release` profile [optimized] target(s) in 0.04s
     Running `target/release/winit-ime-repro`
KeyboardInput[Pressed ] logical=Named(F2) physical=Code(F2)
window.set_ime_allowed(true)
KeyboardInput[Released] logical=Named(F2) physical=Code(F2)
2026-03-17 23:05:43.827 winit-ime-repro[75576:269774467] error messaging the mach port for IMKCFRunLoopWakeUpReliable
KeyboardInput[Pressed ] logical=Character("ㅎ") physical=Code(KeyG)
KeyboardInput[Released] logical=Character("ㅎ") physical=Code(KeyG)
KeyboardInput[Pressed ] logical=Named(Backspace) physical=Code(Backspace)
KeyboardInput[Released] logical=Named(Backspace) physical=Code(Backspace)
IME Enabled
IME Preedit("ㅎ", Some((3, 3)))
IME Preedit("하", Some((3, 3)))
IME Preedit("한", Some((3, 3)))
IME Preedit("한", Some((3, 3)))
IME Preedit("", None)
IME Commit("한")
IME Preedit("", None)
IME Preedit("ㄱ", Some((3, 3)))
IME Preedit("구", Some((3, 3)))
IME Preedit("국", Some((3, 3)))
IME Preedit("국", Some((3, 3)))
IME Preedit("", None)
IME Commit("국")
IME Preedit("", None)
IME Preedit("ㅇ", Some((3, 3)))
IME Preedit("어", Some((3, 3)))
KeyboardInput[Pressed ] logical=Named(Alt) physical=Code(AltLeft)
IME Preedit("어", Some((3, 3)))
IME Preedit("", None)
IME Commit("어")
IME Preedit("", None)
KeyboardInput[Pressed ] logical=Named(Enter) physical=Code(Enter)
KeyboardInput[Released] logical=Named(Enter) physical=Code(Enter)
KeyboardInput[Released] logical=Named(Alt) physical=Code(AltLeft)

Reproduction

https://gist.github.com/umajho/5f42a9cfe49ecfe61d4a9753796d00f2

macOS version

ProductName:		macOS
ProductVersion:		15.7.3
BuildVersion:		24G419

Winit version

0.30.13

[madsmtm]

CC @Random-Scientist for "IME is broken".

(I don't expect you to fix it, just letting you know of yet another case).

[Random-Scientist]

Thanks, already saw these earlier. The list grows...

Honestly there are enough IME specific/implicated issues across the various platforms at present, it might be worth having an issue tag just to keep track of them all.