1.77v

Features

1. Option to set Long Polling for messages sync.
2. Dumped session if it's not required for anonymous users. Should give some performance boost. Let me know if you encounter any issue and I will fix it in less than 24 hours.
3. Chat tabs interface will show user options as go offline/online. Disable enable sound, this applies also to chrome extension.

If you decide to experiment with Long Polling make sure that.

1. You have enabled it in "Synchronisation and sound settings"
2. Connection to server is less than php script execution time. 29 seconds is good start.
3. Internal message sync interval is not very small. 1.5 second is good start. If you want more real time appearance. Reduce it to half second or so. You can also decrease standard "Sync for a new user message, interval in seconds" let say to half second. 0.5 or a little bit less. After one polling request another request will be executed after this value. Good luck with your experimenting.

Bugfix
1. Removed scrollbar in popup if file upload was activated.

execute doc/update_db/update_58.sql for update and follow standard upgrade tutorial. I suggest review your "Synchronisation and sound settings" after update if you have tweaked them before.