Invalid DocType cannot be corrected

[matthias-ronge]

Describe the bug
If the DocType (the top division) contains a type that is unknown in the ruleset, this cannot be corrected using the "Change type of structure element" dialog. Nothing is displayed in the dialog and the list cannot be expanded.

To Reproduce
Steps to reproduce the behavior:

1. Change the DocType in a meta.xml file to something that does not exist in the ruleset (here: MultiVolumeWork, but the ruleset only knows MultivolumeWork).
2. Open the process in the Metadata Editor
3. Right-click on the incorrect structure in Structure Tree and select "Change type of structure element"
4. See: everything is empty and nothing can be chosen

Expected behavior
All divisions permitted at this point should be listed, here—in the case of the topmost division—all permitted doc types.

Screenshots

Release
3.6.0

Desktop (please complete the following information):

• OS: Windows 10
• Firefox 122.0

Additional context
In the case found, the process is a hierarchical superordination, which also already has a linked subordination process. Maybe that plays a role.

[solth]

I just tested this in the current version 3.6.2 - the error only seems to affect parent processes. I couldn't reproduce the issue for processes without children and standalone processes, e.g. those processes had an unknown or undefined document type the list in the "Change doc type" popup wasn't empty and I was able to change the doc type to a valid value. So I guess it has something to do with process hierarchies.