Update of version 1.5.2 break my page

Updating to 1.5.2 breaks my page, I need to remove the plugin directory of ‘Ongoing Events’ to re-activate it.

Events Manager itself has version 5.9.7.3, in parallel I had em-osm and em-cancellation installed but all are currently deactivated, too.

The e-mail of recovery mode delivers the following technical information:

WordPress-Version 5.4
Aktuelles Theme: Catch Wedding Pro (Version 2.2.1)
Aktuelles Plugin: Events Manager – Ongoing Events (Version 1.5.2)
PHP-Version 7.3.16
Fehler-Details
==============
Ein Fehler vom Typ E_ERROR wurde in der Zeile 99 der Datei /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-content/plugins/stonehenge-em-ongoing-events/stonehenge-em-ongoing-events.php verursacht. Fehlermeldung: Uncaught Error: Call to a member function translate() on null in /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-content/plugins/stonehenge-em-ongoing-events/stonehenge-em-ongoing-events.php:99
Stack trace:
#0 /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-content/plugins/stonehenge-em-ongoing-events/stonehenge-em-ongoing-events.php(84): Stonehenge_EM_Ongoing_Events::localize_assets()
#1 /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-includes/class-wp-hook.php(287): Stonehenge_EM_Ongoing_Events::register_assets(‘plugins.php’)
#2 /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#3 /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#4 /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-admin/admin-header.php(104): do_action(‘admin_enqueue_s…’, ‘plugins.php’)
#5 /mnt/web320/d1/64/59145864/htdocs/WordPress_01/wp-admin/plugins.php(486): require_once(‘/mnt/web320/d1/…’)
#6 {main}
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