“New Entry”-Button does not work

Hello,

I have the problem, that the “New Entry”-Button does not work with Edge, Chrome, Firefox etc. – but it works fine with Safari (V14)!

I checked the behaviour also after installing the plugin “Enable jQuery Migrate Helper”. In this case it works with all tested browsers.

What can be the problem?

Thanks,
Thomas

WordPress-Version: 5.5.1 (db: 48748)
WordPress Theme: Nirvana
Aktive Plugins: Array ( [0] => advanced-sidebar-menu/advanced-sidebar-menu.php [1] => amr-shortcode-any-widget/amr-shortcode-any-widget.php [2] => contact-form-7/wp-contact-form-7.php [3] => cookie-notice/cookie-notice.php [4] => cryout-theme-settings/cryout-theme-settings.php [5] => disable-comments/disable-comments.php [6] => easy-table/easy-table.php [7] => enable-jquery-migrate-helper/enable-jquery-migrate-helper.php [8] => event-tickets/event-tickets.php [9] => gwolle-gb/gwolle-gb.php [10] => health-check/health-check.php [11] => limit-login-attempts-reloaded/limit-login-attempts-reloaded.php [12] => polaroid-gallery/polaroid_gallery.php [13] => simple-page-ordering/simple-page-ordering.php [14] => the-events-calendar/the-events-calendar.php [15] => two-factor/two-factor.php [16] => updraftplus/updraftplus.php [17] => wp-math-captcha/wp-math-captcha.php )
PHP-Version: 7.4.11
MySQL-Version: 5.7.30-log
MySQL-Zeichensatz: MySQL-Zeichensatz: utf8mb4
MySQL Column Charset: utf8mb4
MySQL-Tabellen: Vorhandene MySQL-Tabellen:
gwolle_gb_entries
gwolle_gb_log
MySQL / MySQLi: mysqli
MySQL-Variablen: Array ( [character_set_client] => utf8mb4 [character_set_connection] => utf8mb4 [character_set_database] => utf8 [character_set_filesystem] => binary [character_set_results] => utf8mb4 [character_set_server] => utf8 [character_set_system] => utf8 [character_sets_dir] => /opt/mysql-5.7.30/share/charsets/ )
MySQL-Engine: InnoDB

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