The Super Forms - Drag & Drop Form Builder WordPress plugin before 6.0.4 does not escape the bob_czy_panstwa_sprawa_zostala_rozwiazana parameter before outputting it back in an attribute via the super_language_switcher AJAX action, leading to a Reflected Cross-Site Scripting. The action is also lacking CSRF, making the attack easier to perform against any user.
https://wpscan.com/vulnerability/2e2e2478-2488-4c91-8af8-69b07783854f/
https://github.com/RensTillmann/super-forms/commit/c19d65abbe43d9b6359c1bf3498dc697d0c19d02