Possibly related to bug 587292. Currently you can preview and load tabs that aren't in the current tab group - this could be potentially confusing since tab candy is a method for organizing tabs, this breaks that convention.

This doesn't look very good for Windows 7 users and is potentially quite confusing so requesting blocking on this one.

Bug 589888 comment #1 noted that this bug also causes the tabs to overlap while previewing tabs: > Created attachment 468401 [details] > Visualisation of the bug > > The middle tab show actually two tabs, the one on the top is MSN and the second > one (barely visible) is Yahoo

I agree that this is a bug, but do not think it's a blocker, sadly.

(In reply to comment #1) > This doesn't look very good for Windows 7 users and is potentially quite > confusing so requesting blocking on this one. There is one more thing about this bug - when I move mouse to the taskbar, hover on a tab that is not in the current tab group (let's call it "X") and then click on the tab from the current tab group the tab "X" is still displayed in Firefox. Then, when I click the tab "X" the other group become active and the tabs from the previously active tab group dissapear. I agree that previews in the task bar may not be blocking 2.0, but the behaviour described above and mentioned tab overlapping is not what users would like to see in the final version...

We expect bug 605338 to land before FF4.0, and bug 586155 after FF4.0, so punting this to the future.