Tests for experimental_customMergeAllOf

[MarekBodingerBA]

Prerequisites

• I have searched the existing issues
• I understand that providing a SSCCE example is tremendously useful to the maintainers.
• I have read the documentation
• Ideally, I'm providing a sample JSFiddle, Codesandbox.io or preferably a shared playground link demonstrating the issue.

What theme are you using?

utils

Version

5.x

Current Behavior

The experimental_customMergeAllOf feature was introduced in #4308. Later, I discovered some missing code branches and fixed them in #4383.

Following a discussion, we agreed it would be valuable to test whether all functions successfully propagate experimental_customMergeAllOf.

This issue aims to explore the possibility of writing such tests.

Expected Behavior

No response

Steps To Reproduce

No response

Environment

No response

Anything else?

No response