macOS 26: Control + Space input switch fails intermittently

Intermittent failure to switch input source with Control + Space in macOS 26 — requires multiple presses, temporarily resolved by switching windows

After updating to macOS 26, switching input sources via Control + Space became unreliable. The language switch often does not trigger on the first press; sometimes 2–3 presses are required, and occasionally it won’t switch until I change the active window. This occurs across various apps (browsers, messengers, editors). Once I switch to another window or app, subsequent Control + Space presses work on the first try.

Steps to reproduce:

1. Open any app with a text field (e.g., browser or messenger).

2. Start typing using the English input source.

3. Press Control + Space to switch to the Russian input source.

4. Observe that the input source does not change on the first press; sometimes 2–3 presses are needed.

5. Switch the active window/app (Cmd + Tab or click another window), then press Control + Space again.

6. Observe that after changing the active window, the switch starts working on the first press.

Expected result:

Input source should always switch on the first press of the system shortcut Control + Space.

Actual result:

The switch is frequently ignored on the first press in certain windows/apps; sometimes it does not occur until the active window changes.

Environment:

- macOS 26 (issue started after the update)

- MacBook Pro 16” (M1 Pro), built-in keyboard

- Input source switching settings — default

- No third-party software installed that remaps or intercepts hotkeys

Workaround:

Change the active window/app; after that, input source switching starts working.