I solved this by installing SSL as that allowed the ws connection to work properly through the ISP in question.
Any file upload does not work
Freshly installed NodeBB 1.13.3 on Ubuntu 18.04.
All works fine but uploading any file (category, logo, etc) gives the following error in the UI:
In the log the error is as following:
at validateFiles (/home/<user>/nodebb/src/middleware/index.js:107:15)
at Layer.handle [as handle_request] (/home/<user>/nodebb/node_modules/express/lib/router/layer.js:95:5)
at next (/home/<user>/nodebb/node_modules/express/lib/router/route.js:137:13)
at Form.<anonymous> (/home/<user>/nodebb/node_modules/connect-multiparty/index.js:114:7)
at Form.emit (events.js:315:20)
at emitCloseNT (internal/streams/destroy.js:81:10)
at processTicksAndRejections (internal/process/task_queues.js:83:21)
Make sure you are not using nodejs 14.x
Ok, what shall I do now - downgrade nodejs?
ok, I just did a downgrade - now all works fine !!