I'm using Simple Mail v2.83 in Firefox 15.0.

I have problem with automatic synchronization.

I have the following setup:

5 e-mail accounts - first 3 (Account1, Account2, Account3) with automatic synchronization set at 1 minute, and the last 2 (Account4, Account5) with automatic synchronization set at 100 minutes.
When I do manual synchronization everything works ok, and accounts synchronize in order (I see the order in newly implemented progress bar): Account1->Account2->Account3->Account4->Account5.
After that next automatic synchronization for first 3 accounts should occur in 1 minute.
After that one minute has passed, synchronization occurs, but for the last account that was synchronized during manual synchronization (Account5), and it does synchronization for that account 3 times in a row (probably because at that time there are three accounts that should be synchronized (Account1, Account2, Account3) ).
So automatic synchronization for all other accounts, except last one (Account5), as described, never happens.

Also, there's a second problem.
Automatic synchronization (as described above) only happens if Simple Mail is open in Firefox tab, and that tab is the currently active tab.
If that is not the case, automatic synchronization never happens, and the Simple Mail icon in Firefox add-on bar, when mouse pointer is placed over it, shows time since last synhronization which is greater then set automatic synchronization time, and just keep getting bigger since all further automatic synchronization don't occur even if we later open Simple Mail in Firefox tab and keep that tab active.

Thanks for you help, and hope this problem will be resolved soon.