TYPO3 Core

the form configuration file created from form named "Jak dołączyć?"
should become:

/jakdolaczyc.yaml

/jakdoczy.yaml

The biggest pain is that when you have a name with many accented characters the file name becomes unreadable.

It's very easy to fix that like:

$csConverter = GeneralUtility::makeInstance(\TYPO3\CMS\Core\Charset\CharsetConverter::class);
$string = $csConverter->specCharsToASCII('utf-8', $string);

See similar change in Powermail:
https://github.com/einpraegsam/powermail/pull/37/files