4.0.0

What's Changed

• Überarbeitung mit Rexstan by @christophboecker in #143
• TODO etc. abgearbeitet by @christophboecker in #144
• VendorUpdate to 4.1.2 by @skerbis in #150
• Update README.md by @alxndr-w in #151
• Information about custom skin.css in README.md by @alxndr-w in #153
• add code-style workflow by @alxndr-w in #152
• Deprecated-Elemente gelöscht by @christophboecker in #154

Full Changelog: 3.8.0...4.0.0