Whenever I have multiple tabs loaded in Safari I often notice some behaviour which was not present in Safari 5.
Whenever I pre-load several tabs and then switch from one tab to the other, the webpage is not immediately there, I first see a whitish background for half a second after which the website appears. It's not reloaded, as I don't see any network activity, but it just appears. This behaviour is not isolated to certain websites, it happens at random. De-activating my extensions does not solve the issue. Resetting Safari also doesn't.
The console shows the following Safari messages:
Safari: CGContextGetDefaultUserSpaceToDeviceSpaceTransform: invalid context 0x0 Safari: CGContextClipToRect: invalid context 0x0
What can be the cause of this problem and how can I solve this?