Deprecated function: Creation of dynamic property externalhost line 60 of src/Filebrowser.php

hmm... I can't replicate this.
I used an old site that was created under D6 and upgraded all to way to 11.4

Maybe I am missing something obvious, but I don't understand why the property would be created dynamically.

Steps to reproduce:

Install Drupal 8, filebrowser, configure it

Upgrade to Drupal 9 with filebrowser, use it, add some records

Upgrade to Drupal 10.1 with filebrowser cofiguration, use it, add some records

Upgrade to Drupal 10.4 with filebrowser

Upgrade to Drupal 11

Drupal 11 requires PHP 8.3, which has the deprecated dynamic properties, some record carried over from previous Drupals results in needing this patch.