Default "Cmd+\" shortcut has a conflict on macOS Monterey

For the many years I've used 1Password, I have ⌘\ set to "Show 1Password" and ⌘⌥\ set to "Fill Login or Show 1Password". This is the reverse of the defaults, so when setting up on a new computer or clean install, I would go into the 1Password preferences, clear the default shortcuts, and then set them to my preference.

I recently set up a new computer running MacOS 12 Monterey and went to do the same thing. However, after clearing the defaults, when trying to set "Show 1Password" to ⌘\, MacOS gives the following error:

The key combination ⌘\ can't be used!
The key combination "Command + \" can't be used because it's already used by a system-wide keyboard shortcut. (If you really want to use this key combination, most shortcuts can be changed in the Keyboard & Mouse panel in System Preferences.)

It's bizarre, because as far as I can tell this is not a system-wide shortcut. I haven't found anywhere that it does anything (always gives a 'no' beep when I press it), and I've gone through everything in the Keyboard system preference pane and it doesn't appear there either. Furthermore, it's clearly possible to set this as a shortcut, as the default 1Password installation had ⌘\ assigned to "Fill Login or Show 1Password". I've not been able to find any reference or solution to this issue, except for https://apple.stackexchange.com/questions/430314/cant-assign-normal-keyboard-shortcuts-on-monterey-because-its-already-used-by/430526#430526. That was solved by editing the plist file directly.

I was wondering if there is a defaults command I could use to restore the ⌘\ shortcut to "Show 1Password". I notice the 1Password preference file (com.agilebits.onepassword7.plist) contains the keys ShortcutRecorder BrowserActivation and ShortcutRecorder GlobalActivation, but I'm not sure if those are the correct ones to edit, and what values I need if so.

Any help with this would be hugely appreciated. I have a decade or more of muscle memory pressing ⌘\ to activate 1Password, and it's driving me crazy constantly getting beeped at when I do so!

1Password Version: 7.9.1
Extension Version: 7.9.1
OS Version: MacOS 12.0.1