Record collection - adding an item duplicates it [Forge Bug #89695]

[erredeco]

This issue has been copied from https://forge.typo3.org/issues/89097 and it is added here for reference;
I've not tested by myself if it is still valid.

Description

Steps to reproduce:

• Create a new record collection item ( sys_collection table ) in a sysfolder or in the root page
• Add at least one item

Result

The item in the list is doubled (appears twice)

If affects 10.2.0-dev (latest master)
it does not affect 9.5.11
not tested with 8.7.x