"Loading, please wait" when trying to

Hello!

I am trying to create/upload ectivities in H5P in FireFox desktop, but am unable to it as I get a "Loading, please wait" message that doesn't disappear:

I am trying to use the content type Drag the Words, but I am sure it doesn't work for other types.

I am using H5P Version 1.15.0 on WordPress. This feature works in our Moodle.

Any ideas on why this is happening? I have heard hints online it may have something to do with a cross-origin policy.

Many thanks!

Console logs:

JQMIGRATE: Migrate is installed, version 1.4.1 load-scripts.php:8:552
XHRGEThttps://awardls.com/wp-admin/admin-ajax.php?token=34r3342081&action=h5p_...
[HTTP/1.1 200 OK 536ms]

Firefox can't establish a connection to the server at ws://127.0.0.1:5500/ws.
XHRGEThttps://awardls.com/wp-admin/admin-ajax.php?token=34r3342081&action=h5p_...
[HTTP/1.1 200 OK 254ms]

Error while loading script 
error { target: script, isTrusted: true, srcElement: script, currentTarget: script, eventPhase: 2, bubbles: false, cancelable: false, returnValue: true, defaultPrevented: false, composed: false, … }
h5peditor.js:124:23
Error while loading script 
error { target: script, isTrusted: true, srcElement: script, currentTarget: script, eventPhase: 2, bubbles: false, cancelable: false, returnValue: true, defaultPrevented: false, composed: false, … }
h5peditor.js:124:23
Error while loading script 
error { target: script, isTrusted: true, srcElement: script, currentTarget: script, eventPhase: 2, bubbles: false, cancelable: false, returnValue: true, defaultPrevented: false, composed: false, … }
h5peditor.js:124:23
XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 870ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 279ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 260ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 235ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 273ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 269ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 241ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 261ms]

XHRPOSThttps://awardls.com/wp-admin/admin-ajax.php
[HTTP/1.1 200 OK 272ms]