I've been using Opera 15+ along side with Opera 12.17 and I've been having this issue since day one but only on Windows (no problem on Mac)

Every 1/4 (approximately) of the time I open a new tab and type the address, the page won't load. The tab turns white (the speeddial goes away), the address bar becomes blank and it shows the page loading indicator but nothing happens.
After this, the tab becomes unusable so I have to close it and open a new one.

This happens when I run Opera and I have many tabs opened. Some of them will just be like this and if I want to get them back I need to close Opera (since I cannot copy the address in that tab).

This is incredibly annoying, especially sine I want to switch to the new Opera for good (12.xx has huge memory issues).
I kept waiting to see if this will be fixed, I tried normal and portable installation but no luck.And this is happening on both my Windows PCs.

Version: 22.0.1471.50 - Opera is up to date
Update stream: Stable
System: Windows 7 64-bit (WoW64)

Any ideas?