Plugins added by IconMenu can not be removed with "removePlugin"

[dopenguin]

Describe the bug
Like the title describes, plugins added by iconMenu can not be removed with removePlugin.

Expected behavior
I'd expect that any plugins can be removed.

Steps to reproduce

1. Add a button that removes e.g. geoLocation in snowbox
2. Start snowbox
3. Click the button
4. geoLocation is still part of iconMenu and now behaves weirdly