How about with newest version of 115?

I haven't checked yet. There were other issues at the time, so I re-installed version 102. I'm still on that version. Since I made this post, I did confirm that the mail loading process had changed since 102, and that the header did not load until after the email content had completed loading.

One example that was consistent was the gaming company Roll20. Their email content delivery is always slow which demonstrates the issue admirably.

This is https://bugzilla.mozilla.org/show_bug.cgi?id=1840943 which is being worked on

Test builds with patches are available. You can use either:

• beta download https://thunderbird.topicbox.com/groups/beta/T482e51f86e162793-Md9dd8819657f2c81e37bcfd5) - includes instructions
• nightly 119.0a1 build download - https://archive.mozilla.org/pub/thunderbird/nightly/latest-comm-central/) - beta link above has detailed testing instructions

That sounds good! I'll look into that one soon.

I had the same problem with 115.2.2. I left another thread before I saw this one. In my case, it started as a pretty rare thing, but then started happening more often until it became very problematic. Sometimes the emails come up fine. Other times, however, the body of the email comes up without any header. Or, more often, the body of the email comes up with the header from the last email I looked at showing. If I wait long enough, the right header will usually appear, but not always. The problem is that one cannot do anything with the email in that situation since I don't know what will happen if I select Delete, for example. Which email will it delete? I hope this can be fixed soon. I am not seeing it mentioned, however, in the release notes for 115.2.3.

I saw it mentioned in some release notes that Wayne (above) mentioned, in regards to not waiting for slow mail server response before rendering the header.

Yes, there was some mention in notes around a beta for version 118. However, I would not expect that to be released for normal use for some time. This issue does not seem like an issue of slow server response to me. In my case, the body of the email appears immediately. It is only the header that is delayed. If it was the server, it seems like the email body would be the last thing to appear. Also, when the header from the last email appears, it does not appear to be left over from before. It appears to be rendered anew with the new email body, although it may be rendered from some sort of cache. At the same time, the correct header does usually appear after a delay of sometimes several seconds -- so something in the code is still working on getting that header after the email has been presented. I agree with you that, if anything, the headers should be presented before the body if both are not available.

It's nothing to do with server response time.

> The problem is that one cannot do anything with the email in that situation since I don't know what will happen if I select Delete, for example. Which email will it delete?

Just check the trash folder. If it's the wrong one, move it back to the original folder?

Thank you for the suggestion, Wayne. I have been a big supporter of Thunderbird, and you and the team do a great job. However, that does not work for me. Over the years I have started to get numerous newsletters of various kinds, ads from vendors, and political solicitations (if you give to any candidate using their online system, you start getting solicitations from many other candidates you never heard of). When I start in the morning, or come back after a few hours, it is normal for me to have 50-100 emails waiting, most of which are those I noted. Since it is hard to get spam filters to work reliably, I have developed a process where I can scan through my emails at high speed: delete the political ones right away, scan newsletters in a few seconds to see if I want to read any articles, and generally dispense with all non critical emails in few minutes while still noting and absorbing anything that interests me. This has worked well for me. However, if I have to wait even an extra second or so for the full email to show, or have to deal with which email will delete and make corrections, it throws that process completely off -- dramatically reducing my productivity. That is why this particular issue is important for me. It may not be as critical for most TB users. Again, I appreciate that the TB team has made the effort to modernize the code base and provide new features. That is very important for the future of the product. I hope these last remaining gremlins can be solved soon.