TYPO3 Core

When editing a flexform that has an IRRE-ELement in it a JavaScript-Error occurs on opening (toggling) the IRRE Element

TypeError: e is null

This error breaks the functionality of textfields (type = "input") within the IRRE Element. These don't have the "x" for deleting the content in it, nor is the content saved to DB.

After a short debugging I found out it is related to https://forge.typo3.org/issues/91183

The ID of an element contained a "." (dot) from the concatination of various information including the name of the field in the flexform (settings.whatsoever). This throws the error in "nprogress.js" as there is a call to "document.queryselector" which cannot handle IDs with dots as this will be interpreted as "has id AND className".

Since "nprogress.js" is a third-party-library I think it can't be fixed there.

As dots in the ID of a HTML-element is generally not a good idea, maybe these could be stripped completly as the form is built?

If necessary I can provide more information on this, feel free to contact me.