TYPO3 Core

The DOM object identifier that are created for nested elements of Inline Releational Record Editing contains invalid characters. Object identifiers are use in IRRE to determine each level of nestification, examle:
data¹¹[tx_irretutorial_1nff_offer]⁴[prices][tx_irretutorial_1nff_price]⁷

JavaScript methods that are executing CSS selections, will not work anymore (i.e. currently deleting child records in the forms view is not possible anymore). It's not a problem of the JavaScript frameworks like prototype.js, the reason are the invalid characters.

However the character "[" and "]" are invalid for being used as DOM object identifier. Thus, the separator has to be changed and accordant parts in the Core have to be adjusted, example:
data-11-tx_irretutorial_1nff_offer-4-prices-tx_irretutorial_1nff_price-7

(issue imported from #M12327)