There seems to be a slowness issue when posting a comment in the forum or sending a message. When you do either it takes a while before the browser resets to the page you were just at. The comment/message is actually posted/sent immediately (i.e. you can close the tab or go to another part of the forum) but the browser doesn't understand it was posted until about a minute later because the server isn't telling it so. So the page isn't reset to back where you were before.
I'm working on it and I'll post again here when I think it's resolved.
I should have said, "I'll post here whether it's resolved or not." I applied an easy fix to the forum that I hoped would work but alas, it didn't work. Sending personal messages takes a full minute. Posting topics or replies appears to sometimes happen quickly, sometimes not. At least, that's the case for me.
You can still send messages and posts and they do seem to happen quickly. I can tell this because you can go to other places in the forum while it appears to be still sending and come back and the message/post will be there. I think that the problem is the server isn't telling the browser it's done posting or at least the forum software isn't. I think the browser eventually times out waiting and the page refreshes showing the change. There doesn't seem to be a pattern here or not one that I've found yet.
I know it's an annoying bug, but please be patient while I keep working on it. If you're worried about losing a post or a message, I suggest you copy/paste the post into your favourite editor like Notepad in Windows (ewww) or Kate in Plasma to give two examples. Don't use a word processor, you want the text to remain in plain text state. Putting it in a word processor and pasting back to the forum will result in ugliness.
If anyone notices things working better for you, please send me a message. Feel free to send me a test message or post in the 'Testing Grounds' board in the 'General (Non-Linux)' category to try out posting if you have nothing to post elsewhere.
Also, feel free to send me a test message, and then another to report the result. After that, please only send me a message if something changes for you. There's no need to keep sending me messages saying it still doesn't work. I likely already know that from my own testing and the problem will likely continue until I have a chance to try other fixes. I'll let you know here when I do maintenance and it seems to fix it for me, and then you can test again and report the results to me.
Thanks for your help!
I neglected to post this update long before now.
Anyway, this matter seems to have resolved itself when I set up a new LAMP server with SMF and restored the database. I'm still not sure what happened or why but I'm just pleased we no longer have that problem.