Comment 46 for bug 927515

From the comments above it looks like there could be several distinct causes of Thunderbird running at 100%.

In my case, I have just upgraded to Raring and the situation has got worse. It now happens pretty much every time I try to minimise or close Thunderbird. Thunderbird will just sit there for hours running at 100%. For me it's worse than that because I use ibus to switch languages and it causes ibus to refresh itself continuously too (see bug #1162008), thus making the computer practically unusable. My key observations are that:

- Now I have upgraded to Raring, this 100% cpu usage is (sometimes) happening when I minimise Nautilus or Firefox too. When this happens, compiz is also near the top of top.
- I have tried using the default xorg graphics drivers and the proprietary nvidia ones, and the issue is the same.
- My colleagues that have similar setups to me (same graphics card, 64bit, similar processors) don't have the same problem. However, I am the only one that has an encrypted home directory.

So, to me this implies that the root cause is some incompatibility between an encrypted home and compiz/Unity, which Thunderbird also happens to be a victim of too. It may just be that Thunderbird tries to write more configuration/database stuff to the (encrypted) home directory when it is minimised than Nautilus or Firefox and so it's a lot more noticeable for Thunderbird than for the others.