The error is modulemanager error Unable to load module 'push_appserver_apns': ...ody/external-modules/mod_push_appserver_apns/mod_push_appserver_apns.lua:197: unexpected symbol near '?'
Replacing that statement with priority = summary["last-message-body"] ~= nil and "high" or "silent"; makes it work.
https://github.com/tmolitor-stud-tu/mod_push_appserver/blob/98b2aea716ac72b899eb8825d05478e7d1674072/mod_push_appserver_apns/mod_push_appserver_apns.lua#L197
The error is
modulemanager error Unable to load module 'push_appserver_apns': ...ody/external-modules/mod_push_appserver_apns/mod_push_appserver_apns.lua:197: unexpected symbol near '?'
Replacing that statement with
priority = summary["last-message-body"] ~= nil and "high" or "silent";
makes it work.Would you like me to submit a PR?