On Sat, Feb 13, 2021 at 02:50:47PM +0200, Danil Smirnov wrote:
Hi everyone and Abhilash in particular :)
I've faced a case when Hypirkitty is unable to chain messages into a thread: https://wlug.mailman3.com/hyperkitty/list/wlug@lists.wlug.org/
[..] It's a quite disappointment as GMail does show them correctly - as a single thread.
As per my small investigation, a subscriber Robert N. Evans seems to have "In-Reply-To" headers stripped from the messages that probably causes the thread to break.
I wonder if Hyperkitty is able to leverage some other method to combine the thread correctly in this case?
There are two common methods to group messages into threads:
Using the "In-Reply-To:" header. (The "correct" approach. Downside: gives false negatives if users strip those headers, as you've seen.)
Using the "Subject:" header. (A heuristic approach. Downside: gives false positives if users start a new thread with the same subject as an older thread.)
I believe Gmail uses the "Subject:" header. That would explain why Gmail was able to recognise Robert N. Evans's messages as part of the thread even though they lacked the "In-Reply-To:" header.
I don't know if Hyperkitty allows threading using "Subject:" matching, but if so then that would probably solve your problem.
Sam
-- A: When it messes up the order in which people normally read text. Q: When is top-posting a bad thing?
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