Duplicate default shortcuts: ⌘= / ⌘- bound to both Zoom In/Out and Markdown Viewer: Zoom In/Out; zoom-in unreachable on non-US layouts

[austinywang]

User report

again two same bindings

in mac terminal it works fine, in warp i have to press cmd + shift + + and it works. in cmux it doesnt work

(Reporter is on a non-US layout where + is not produced by Shift+=; "it" = zooming in.)

Their screenshot of Settings → Keyboard Shortcuts shows:

Action	Default
Reload Page	⌘R
Zoom In	⌘=
Zoom Out	⌘-
Actual Size	⌘0
Markdown Viewer: Zoom In	⌘=
Markdown Viewer: Zoom Out	⌘-

Problems

1. Conflicting defaults shipped again. "Markdown Viewer: Zoom In/Out" (added alongside the markdown viewer font-size/zoom controls, e.g. Add font-size/zoom control to the markdown viewer #5163) ships with the same ⌘= / ⌘- defaults as the existing Zoom In / Zoom Out actions. This is the second instance of this class after Cmd+R / Cmd+Shift+R defaults for Rename Tab / Rename Workspace conflict with browser reload and should be unbound by default #3467 (Rename Tab / Rename Workspace ⌘R colliding with browser Reload Page), which was resolved by unbinding the colliding defaults. If the markdown-viewer pair is intentionally context-scoped (only active while a markdown viewer is focused), the shortcuts UI gives no indication of that — it renders as a plain conflict, while the shortcut recorder itself refuses user-entered conflicts (Shortcut recorder silently rejects bare keys and conflicting shortcuts without explaining why #2988, Shortcut recorder incorrectly blocks re-assigning Cmd+R to context-specific action after unbinding #3486). Either unbind/re-scope the defaults or label context-scoped duplicates in the UI.

2. Zoom-in still unreachable on non-US layouts. On the reporter's layout, zoom-in does not work at all: Terminal.app handles it fine, Warp works via ⌘⇧+, cmux does nothing. Likely the same root cause as Alternative keyboard layouts not considered for hotkeys #3362 / Zoom in (increase font size) not working — zoom out works fine #1456 — PR Fix terminal zoom on non-US ISO keyboard layouts #4302 (open) fixes the terminal path for ISO layouts and Fix markdown/browser Cmd zoom on non-US keyboard layouts #5394 fixed the markdown/browser path. Whatever ⌘+ keystroke the layout produces should resolve to zoom-in.

Expected

• No two actions ship with identical default shortcuts, or context-scoped duplicates are explicitly indicated in Settings → Keyboard Shortcuts.
• Zoom-in works on non-US keyboard layouts (parity with Terminal.app / Warp).

[allenchuang]

for some reason i can zoom in / out to increase font size on the CLI (terminal) through ⌘= / ⌘- but not on MD preview or files

[Angel-M-R]

Confirmed with a Spanish ISO keyboard layout.

Environment:

• cmux 0.64.17 (97), commit 9ed29d8
• macOS 26.5.1 (25F80)
• Spanish ISO input source

Reproduction:

1. Focus a terminal pane in cmux.
2. With the Spanish input source, press Cmd plus using the dedicated + key.
3. Nothing happens.
4. Switch the macOS input source to English and press Cmd plus: terminal font size increases normally.
5. Ghostty standalone recognizes Cmd plus correctly with the Spanish input source.

The Spanish + key appears to occupy the physical key position that cmux treats as ]. cmux captures Cmd+] for focusHistoryForward before the event reaches the embedded Ghostty terminal.

This workaround fixes the problem immediately:

{
  "shortcuts": {
    "bindings": {
      "focusHistoryBack": null,
      "focusHistoryForward": null
    }
  }
}

After running cmux reload-config, Cmd plus works with the Spanish layout. This suggests the non-US terminal zoom failure is caused by app-level physical-key shortcut matching/routing, rather than a missing Ghostty zoom binding.