Unable to disable Mousepad Spell Checking

No spell checking packages are installed (or desired) on the system.

In Mousepad, Edit --> Preferences --> Plugins only shows "Shortcuts Editor", but not "Spell Checking", in contrast to the documentation: (https://docs.xfce.org/apps/mousepad/start#screenshots)

Because "Spell Checking" is missing in Mousepad Preferences Plugins, it is not possible to disable Spell Checking in Mousepad, which in turn results in an error message being issued every time Mousepad is started:

Mousepad-Message: 16:27:17.143: Failed to load plugin "mousepad-plugin-gspell": libgspell-1.so.3: cannot open shared object file: No such file or directory

Particularly in the case where no spell checking packages are installed, it should be possible to disable the Spell Checking Plugin in Mousepad Preferences, so that no such error messages appear.