User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:14.0) Gecko/20100101 Firefox/14.0.1 Build ID: 20120713134347 Steps to reproduce: Fairly reliably when synchronizing folders ("work offline" or "download/sync now")... Actual results: ...just about every folder reports via an incredibly irritating and useless modal dialog "Alert: The operation failed because another operation is using the folder. Please wait for that operation to finish and then try again." Expected results: There is never an excuse for a modal dialog. Ever. Particularly one that stops background processes. Especially one that steals focus from whatever else I'm doing, like composing a message. A summary, non-modal dialog may be useful if I'm performing a disconnect operation along the lines of "the following mailboxes were not synced because another operation was using them." That alert might be justified as I may be disconnecting and might want to know whether I got all my mail off my IMAP server and onto my local device for use while disconnected. If I'm not disconnecting then there's no earthly reason why a normal user would care whether another operation was using the folder; Thunderbird should silently, obediently retry the sync operation later. I'm not debugging the sync process, I just want my mail. There's nothing I can do about the "other operation using the folder" but be annoyed and try again later - so why not simply do that for me silently in the background and avoid the annoyance.
is this not a duplicate? https://bugzilla.mozilla.org/buglist.cgi?query_format=advanced;short_desc_type=allwordssubstr;resolution=---;type0-0-0=nowords;value0-0-0=count%20counts;product=MailNews%20Core;product=Thunderbird;short_desc=modal;list_id=4364826
Yep - it is a duplicate of bug 288896 that was first reported in 2005 and still hasn't been fixed. The OP of that bug is absolutely correct - these modal dialogs have to go! It is kind of amazing that such a basic UI failure has persisted for so many years (at least 7!).