TYPO3 Core

If an e.g. content element uses a column to provide inline elements those elements are handled different when not directly defined in the original config but the columnsOverrides.

The basic column is defined as "type => passthrough".

Within e.g. 2 different elements you can then define the proper "type => inline" which might vary between the elements to use different columns.
Now the issue occurs:
If you create the parent record along with its inline element, the TCA is rendered perfectly fine.
1. When deleting the parent though the child, inline element is not set deleted (even with cascading delete activated)
2. When copying the parent the child is not duplicated or left out in the copy action, but actually changes the parent reference to the new record. This means the connection between the child and original parent is lost

Side notes for pachter (which is eventually me):
- EXT:styleguide should provide some fast accessible table/column setup
- check for breaking state: if this is patched and provides a fix/ changed behavior it could potentially impact instances that did not know of this misbehavior and affect those as the saving/moving/copying/deleting of records would be changed.