Starting build 101216 and as well present in the latest r10238 I see following bug. If I have a couple of tabs open and randomly switch between tabs the content doesn't pop from cache, but instead the entire page reloads pulling the data from the net. This is highly annoying and unproductive. I have not seen such a crazy behavior in other browsers. Going back to r101160 resolves the issue.
I forgot to mention that this bug triggers once you close the first of the tabs (possibly any given tab). After that picking any of the remaining tabs leads to a white screen while the content is reloaded from the net and depending on the speed of the connection it takes 1-3 seconds before the old page becomes visible. It seems it also auto-submits the form on the reloaded page. I found out that, while I was submitting this bug and tried to reproduce it again. When I came back to the form with the bug it gave me red alert that the form was already submitted, instead of showing where I left off before switching the tab.
*** This bug has been marked as a duplicate of bug 73183 ***