When you select a folder which has exactly the number of messages that fit on the message list view the application hangs. When the number of messages is less (no need for a scrollbar) it works as expected. When the number of messages is such that at least one is scrolled out, the app works as expected. When you happen to have your inbox with that many messages you can't use the mail component anymore because hangs the app hangs immediately. I can't confirm this, but I belive that the hang occurs when the last message is selected.
I'm not able to reproduce this... Please try with a current build, and if you still see the problem, please provide build id, type of account, and any details that might aide in reproducing the problem.
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