If I recall correctly, there is a bug that describes that preview pane returns if the last folder selected (of any name) is empty, or if the account is selected. If so, perhaps this can be duped to an older bug
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.7) Gecko/20100204 Shredder/3.0.2pre
t-wayne Thanks for the steps in comment 20. I can reproduce as follows:
1. click *trash* folder
2. f8
3. empty trash
4. file|exit
5. startup
preview pane returns.
If I recall correctly, there is a bug that describes that preview pane returns if the last folder selected (of any name) is empty, or if the account is selected. If so, perhaps this can be duped to an older bug
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.7) Gecko/20100204 Shredder/3.0.2pre