Hello!
Here's the problem: website needs to be refreshed twice to see a new content, otherwise user will see a cached version of the website. It's quite troublesome when you have a live website and users need an instant update when a new post appears. I illustrated the problem with a video:
After posting, site automatically refreshes itself but there's still 'No new threads'. Only when you refresh it manually for the second time, you'll see a new thread. This is happening on Altervista only, I have tested the same website on 000webhost before. It's not a browser/device issue, I have tested it on many configurations and all users can't see their new post after posting.