TYPO3 Core

If you change the location of a file inside TYPO3, you would usually expect that the file abstraction layer will internally handle the changes, so the file can still be accessed from the frontend. (no hard-wired paths to the original file location)

This is not the case, if you change the location of a YAML form. If you go to the filelist and change the location of a yaml form, frontend pages that are using this form in a plugin will now break, because the forms location can't be resolved anymore.
I suppose this is because of the flexform configuration of the form plugin. - The flexform saves the original file location to the yaml instead of utilizing FAL.