static SHARED_CLIPBOARD: OnceLock<Option<Mutex<Clipboard>>>Expand description
A shared clipboard for use by the DefaultClipboardDelegate.
This is protected by a mutex so that it can only be used by one thread at a time.
The arboard documentation suggests that more than one thread shouldn’t try to access
the Windows clipboard at a time. See https://docs.rs/arboard/latest/arboard/struct.Clipboard.html.