Rescue core module for apache seems to be broken

Debug information:

root@server1:~# /usr/local/ispconfig/server/server.sh
08.04.2022-09:20 - WARNING - httpd is down! Try rescue httpd (try:1)...
08.04.2022-09:20 - WARNING - Invalid init command action stop
sh: -c: line 0: syntax error near unexpected token `&&'
sh: -c: line 0: ` && (sleep 3; kill $!; sleep 2; kill -9 $!) &> /dev/null'
08.04.2022-09:20 - WARNING - Invalid init command action start
PHP Warning:  exec(): Cannot execute a blank command in /usr/local/ispconfig/server/mods-available/rescue_core_module.inc.php on line 478
08.04.2022-09:20 - DEBUG [plugins.inc:155] - Calling function 'check_phpini_changes' from plugin 'webserver_plugin' raised by action 'server_plugins_loaded'.
08.04.2022-09:20 - DEBUG [server:217] - Remove Lock: /usr/local/ispconfig/server/temp/.ispconfig_lock
finished server.php.

This seems to happen only when no other actions were processed by server.sh.