Hi - I'm experiencing an issue with custom content types in document set subfolders in Sharepoint 365.
I've created two custom content types - one derived from Folder, and one from Document Set. Both have been added to the document library, and "Allow management of content types" is set to yes.
While at the top level of a document library, or the top level of a document set, the custom content types appear in the New menu as expected, but after navigating to any subfolder of a document set, the content types are missing; only the default (Folder, Word document, Excel workbook, etc) are available.
This was working correctly last week (March 2022).