Peter Davis <pfd@pfdstudio.com> writes:

> Thanks for all the help and suggestions, everyone. Setting
> gnus-build-sparse-threads to t does seem to do what I was looking for,
> but now opening a group takes too long. So I think I'll drop back to
> *not* showing previously read messages in the thread, and using 'A T'
> when I want to see the history.

Change the value to "some". It is much quicker:

,----
| gnus-build-sparse-threads is a variable defined in `gnus-sum.el'.
| Its value is some
| Original value was nil
| 
| Documentation:
| *If non-nil, fill in the gaps in threads.
| If `some', only fill in the gaps that are needed to tie loose threads
| together.  If `more', fill in all leaf nodes that Gnus can find.  If
| non-nil and non-`some', fill in all gaps that Gnus manages to guess
`----

Charles

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