Keyboard shortcuts do not conflict with common browser or system defaults

Extension shortcuts that collide with Chrome-reserved combinations (Ctrl+T, Ctrl+W, Ctrl+Shift+N, Ctrl+L, Ctrl+R, F5) get silently dropped by Chrome during registration — the manifest declares them, the extension looks configured, but the shortcut never fires. Users file bug reports about features that do not work, developers waste cycles investigating non-bugs, and support costs climb. Conflicts with OS-level shortcuts (Cmd+Space, Win+L) cannot be overridden at all and make the extension appear broken on specific platforms.

Use Alt+Shift+{Key} or MacCtrl+Shift+{Key} patterns in manifest.json — these bindings are reliably available to extensions on all platforms Chrome supports. Declare platform variants explicitly:

{
  "commands": {
    "toggle-feature": {
      "suggested_key": { "default": "Alt+Shift+F", "mac": "MacCtrl+Shift+F" },
      "description": "Toggle feature"
    }
  }
}

Verify registration in a clean Chrome profile at chrome://extensions/shortcuts.

• ID: extension-ux-performance.browser-ux.keyboard-shortcuts-safe

• Severity: high

• What to look for: Examine the commands section of manifest.json. For each keyboard shortcut defined (suggested_key), check it against known browser shortcuts that extensions should not override. Particularly problematic combinations: Ctrl+T (new tab), Ctrl+W (close tab), Ctrl+Shift+N (incognito), Ctrl+L (address bar), Ctrl+R (reload), Ctrl+H (history), F5 (reload), Alt+F4 (close window on Windows). Also check for shortcuts that conflict with common system shortcuts on macOS (Cmd+Space for Spotlight) or Windows (Win+L for lock screen). Count all instances found and enumerate each.

• Pass criteria: All extension keyboard shortcuts use combinations that Chrome allows extensions to register and that do not overlap with reserved browser shortcuts. The recommended pattern is Alt+Shift+{Key} for cross-platform compatibility. No shortcuts attempt to override globally reserved key combinations. At least 1 implementation must be confirmed.

• Fail criteria: Extension manifest.json declares a shortcut that conflicts with a browser-reserved combination (Chrome silently ignores shortcuts it cannot register, but the extension may appear non-functional). Shortcuts use single modifier keys (Ctrl+{letter}) that commonly conflict with browser actions.

• Skip (N/A) when: The extension declares no commands in the manifest (no keyboard shortcuts).

• Cross-reference: The popup-renders-fast check in Popup Responsiveness verifies that keyboard-triggered popup openings are equally fast.

• Detail on fail: Name the conflicting shortcut. Example: "Manifest declares Ctrl+Shift+N as extension shortcut — this is reserved for incognito window, Chrome will not register it" or "Ctrl+R shortcut conflicts with page reload — users expecting reload will trigger extension action instead."

• Remediation: Use Alt+Shift+{Key} patterns which are available to extensions across platforms:

  {
    "commands": {
      "toggle-feature": {
        "suggested_key": {
          "default": "Alt+Shift+F",
          "mac": "MacCtrl+Shift+F"
        },
        "description": "Toggle extension feature"
      }
    }
  }
  

  Test your shortcuts in a clean Chrome profile to verify they register correctly. Users can also re-map shortcuts at chrome://extensions/shortcuts.