[ratiolat]

I've hit "Thunderbird is slow" many times and it has turned out that the reason is that GMail is applying rate limiting.

I originally switched from Apple mail because I thought Apple mail could not handle my gmail.

https://support.google.com/a/answer/1071518?hl=en

[efreak]

Gmail has all sorts of limits people don't realize, including a limit on the number of incoming emails (1/s, which does seem pretty reasonable).