On Mon, 19 Aug 2019, Sarah k Alawami wrote:

I have over 200 thousand so that might be an issue ther at least as far as gmail. And no I'm not clearing any of it, at least not yet.

In a single folder, or spread across the IMAP folders in that account?

If I recall correctly, gmail exposes virtual IMAP folders. So everything in your inbox acts as if it is replicated in the allmail folder. And a few other cases of that sort of thing. I wonder if Thunderbird is seeing those as separate folders, and trying to process them as such? That is a wild shot in the dark, as I have never used Thunderbird, and all my gmail IMAP access is via mail programs that behave well with it.

Luke