On mac, Ctrl + Shift + C
uses keyup listener instead of keydown. So you have to have the ‘C’ key lifted first to trigger cloze.
Because I normally go Cmd > Shift > C > Cmd up > Shift up > C up
, I thought the cloze shortcut was broken until I looked at the code.
Related issue: Fix 'same cloze' shortcut on macOS · Issue #1748 · ankitects/anki · GitHub