Fehlermeldung WordPress Widget-Seite

können Sie uns eventuell weiterhelfen? Plötzlich geht die Widgets-Seite in WordPress bei uns nicht mehr auf:

Quelle: https://www.ligablatt.de/wp-admin/widgets.php

image.png
TypeError: Cannot read properties of undefined (reading ‚_expiration-date-type‘)
at t.value (https://www.ligablatt.de/wp-content/plugins/post-expirator/assets/js/gutenberg-panel.js?ver=2.6.2:1:6477)
at t.value (https://www.ligablatt.de/wp-content/plugins/post-expirator/assets/js/gutenberg-panel.js?ver=2.6.2:1:2901)
at pe (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:70:303)
at rh (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:98:284)
at zj (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:228:490)
at Th (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:152:223)
at tj (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:152:152)
at Te (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:146:151)
at Ja (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:224:381)
at md (https://c0.wp.com/c/5.8.1/wp-includes/js/dist/vendor/react-dom.min.js:173:43)

Die Seite, für die ich Hilfe brauche: [Anmelden, um den Link zu sehen]