Critical Error shown

We get a critical error shown on Foo Gallery
We have many galleries (245) on 13 pages, but on each page, only the first gallery is shown in the WP Backend.
It does not affect the appearance on the website itself. Here everything works fine and is displayed correctly.

It has nothing to do with plugins or themes (tests were made).

Thank you in advance for your help!

Here is the error:

WordPress-Version 5.9.3
Aktives Theme: Divi Child Theme (Version 1.0.0) Aktuelles Plugin: FooGallery (Version 2.1.34) PHP-Version 8.0.18

Fehler-Details
==============
Ein Fehler vom Typ E_ERROR wurde in der Zeile 397 der Datei /srv/www/web2558/htdocs/wp-content/plugins/foogallery/includes/class-foogallery.php verursacht. Fehlermeldung: Uncaught ValueError: Unknown format specifier "B" in /srv/www/web2558/htdocs/wp-content/plugins/foogallery/includes/class-foogallery.php:397
Stack trace:
#0 /srv/www/web2558/htdocs/wp-content/plugins/foogallery/includes/class-foogallery.php(397): sprintf()
#1 /srv/www/web2558/htdocs/wp-content/plugins/foogallery/includes/admin/class-columns.php(51): FooGallery->image_count()
#2 /srv/www/web2558/htdocs/wp-includes/class-wp-hook.php(309): FooGallery_Admin_Columns->gallery_custom_column_content()
#3 /srv/www/web2558/htdocs/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#4 /srv/www/web2558/htdocs/wp-includes/plugin.php(474): WP_Hook->do_action()
#5 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-posts-list-table.php(1332): do_action()
#6 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-list-table.php(1450): WP_Posts_List_Table->column_default()
#7 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-posts-list-table.php(1384): WP_List_Table->single_row_columns()
#8 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-posts-list-table.php(795): WP_Posts_List_Table->single_row()
#9 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-posts-list-table.php(772): WP_Posts_List_Table->_display_rows()
#10 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-list-table.php(1362): WP_Posts_List_Table->display_rows()
#11 /srv/www/web2558/htdocs/wp-admin/includes/class-wp-list-table.php(1289): WP_List_Table->display_rows_or_placeholder()
#12 /srv/www/web2558/htdocs/wp-admin/edit.php(477): WP_List_Table->display()
#13 {main}
  thrown

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