Technical error on saving popup

Hello,

I re-installed Popup Builder to activate a client’s «We will be on holiday»-message. The site is running on Salient theme and WP Bakery in classic mode. All plugins etc. updated to latest versions. When I duplicate the previous’ summers popup and work on it, it opens in the Block editor, no question asked (!). I can work on the raw code alright, but on saving the site gets shot down.
Why is there no warning or a choice syaing: do you really want edit using the Block editor?

Wenn du Hilfe bei diesem Problem suchst, wirst du möglicherweise nach einigen der folgenden Informationen gefragt:
WordPress-Version 7.0
Aktives Theme: Salient (Version 18.2.1)
Aktuelles Plugin: Popup Builder - Create highly converting, mobile friendly marketing popups. (Version 4.4.4)
PHP-Version 8.3.31

Fehler-Details
==============
Ein Fehler vom Typ E_ERROR wurde in der Zeile 1329 der Datei /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-content/plugins/popup-builder/com/classes/Actions.php verursacht. Fehlermeldung: Uncaught Error: Call to a member function getType() on string in /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-content/plugins/popup-builder/com/classes/Actions.php:1329
Stack trace:
#0 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-includes/class-wp-hook.php(341): sgpb\Actions->popupsTableColumnsValues('type', 87711)
#1 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-includes/class-wp-hook.php(365): WP_Hook->apply_filters('', Array)
#2 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-includes/plugin.php(522): WP_Hook->do_action(Array)
#3 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-posts-list-table.php(1407): do_action('manage_popupbui...', 'type', 87711)
#4 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-list-table.php(1796): WP_Posts_List_Table->column_default(Object(WP_Post), 'type')
#5 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-posts-list-table.php(1441): WP_List_Table->single_row_columns(Object(WP_Post))
#6 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-posts-list-table.php(838): WP_Posts_List_Table->single_row(Object(WP_Post), 0)
#7 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-posts-list-table.php(814): WP_Posts_List_Table->_display_rows(Array, 0)
#8 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-list-table.php(1706): WP_Posts_List_Table->display_rows()
#9 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/includes/class-wp-list-table.php(1630): WP_List_Table->display_rows_or_placeholder()
#10 /home/httpd/vhosts/woodwork.ch/httpsdocs/wp-admin/edit.php(503): WP_List_Table->display()
#11 {main}
thrown

Do you have a solution for this issue?
Thank you!

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