When creating a custom tab in the Roblox Studio ribbon toolbar using plugins, buttons added to the tab are duplicated after entering test mode (Play, Play Here, etc.).
This duplication happens every time testing is started, and does not disappear until the session is stopped or Studio is restarted.
In Studio (Not Testing):
While Testing:
This issue occurs regardless of which plugin creates the tab and can be reproduced in a blank baseplate.
Expected behavior
The custom tab should remain unchanged during test mode. Plugin buttons should not be duplicated when entering or exiting test sessions in Studio.