Seems like after upgrading to mentions withmention groups
function, the anonymous posting will cause conflicts like this:
POST https://site.name/api/posts
<br />
<b>Warning</b>: Attempt to read property "display_name" on null in <b>/www/wwwroot/site.name/vendor/flarum/mentions/src/Notification/UserMentionedBlueprint.php</b> on line <b>69</b><br />
<br />
<b>Warning</b>: Attempt to read property "display_name" on null in <b>/www/wwwroot/site.name/vendor/flarum/mentions/src/Notification/GroupMentionedBlueprint.php</b> on line <b>69</b><br />
<br />
<b>Fatal error</b>: Uncaught Laminas\HttpHandlerRunner\Exception\EmitterException: Output has been emitted previously; cannot emit response in /www/wwwroot/site.name/vendor/laminas/laminas-httphandlerrunner/src/Exception/EmitterException.php:24
Stack trace:
#0 /www/wwwroot/site.name/vendor/laminas/laminas-httphandlerrunner/src/Emitter/SapiEmitterTrait.php(40): Laminas\HttpHandlerRunner\Exception\EmitterException::forOutputSent()