Vincent Le Goff <vincent.legoff.srs@...>
I dare to create a new thread to discuss this issue more. So just to recap: some of us (not all of us) have experienced significant lags in Thunderbird over a period ranging from a few weeks to a year or so. Hard to pinpoint the issue and since a lot of users didn't experience this, the issue was neither critical not even proven (hard to prove a lag, by all means).
This could apply to other email clients, it seems. As far as I'm concerned, the problem was that my inbox was crowded. Last I checked I had around 12K emails in only one folder and the older emails had been sent in 2009. I had gone over cleaning up this folder and removing what I didn't care to keep, but there were a lot of emails I simply archived because I wanted to keep a track. And because I'm using iMap (several devices to keep in sync, I couldn't very well use Pop3), these emails were sent to every client.
A (bug) was discovered on Gmail accounts. Deleted emails, by default, weren't deleted at all, just kept in a separate folder in Gmail which was a poor fix and didn't exactly solve my problem. But more importantly, I went to the Gmail settings and asked it to only send me 1000 emails in a single folder at most. And after a painful and slow client sync, I find Thunderbird so much more responsive. Was it really all that took? And if so, who's responsible? Is it logical for NVDA to lag that much in a simple list when the said list has around 10K entries? Maybe yes, maybe not. Maybe Thunderbird itself, despite its "caching" and "compacting" doesn't handle the situation very well, at least for users relying on assistive technology. It might be worth reporting their way, but it probably is worth discussing here beforehand. Besides, Thunderbird might not be the only one suffering from this issue. And this "fix" might not fix anything for others. Again, worth talking about.
The setting that changed my life was in Gmail: so login to gmail.com, open settings / POP3 and iMAP sync (sorry for the labels that might be somewhat different, Gmail is in French on my account), and check the options on "when a message is marked as deleted". Just below you will find another setting to limit the number of emails per folder. By default there's no limit, but if you check a limit Gmail offers you 1000 emails per folder at most. This seems to be a good alternative. The remaining (for me!) 11K emails aren't deleted, but Gmail keeps them on its server and doesn't send them to the client except if you search (Thunderbird allows to run a full search on the server).