I'm having another strange problem : whenever I've selected a mail folder that is not my inbox, all the CSS styles apply correctly (bold font for folders containing unread mail, and on-hover highlighting when dragging a message into a folder, for instance).
However, when it is the main "inbox" folder that is selected, those styles don't apply : folders with unread mails display the correct number of unread message, but no bold font, and there is no folder highlighting when dragging a message onto it.
I've checked the HTML source in both cases, and there is no difference whatsoever (diff'ed the files).
Any input appreciated.