Fatal error: Array and string offset access syntax with curly braces is no longer supported in /home/httpd/vhosts/speerli.de/eizzy.de/wp-includes/blocks/index.php on line 2

Fatal error: Uncaught Error: Call to a member function set() on null in /home/httpd/vhosts/speerli.de/eizzy.de/wp-includes/l10n.php:850
Stack trace:
#0 /home/httpd/vhosts/speerli.de/eizzy.de/wp-includes/l10n.php(953): load_textdomain('default', '/home/httpd/vho...', 'de_DE')
#1 /home/httpd/vhosts/speerli.de/eizzy.de/wp-includes/class-wp-fatal-error-handler.php(49): load_default_textdomain()
#2 [internal function]: WP_Fatal_Error_Handler->handle()
#3 {main}
  thrown in /home/httpd/vhosts/speerli.de/eizzy.de/wp-includes/l10n.php on line 850