Found a bug with custom widgets’ Context Pane.
When clicking between one custom widget to another, the prop fields for the custom widget carry across. For example, the LOOPER v1 widget only has the Loop List prop, but if I click the LOOPER v2 then LOOPER v1, it displays the following:
This happens with other custom widgets as well. Clicking between Step and Widget (at the top of the Context Pane) resets it properly.