New mail -> 'un-collapses' thread ... Can I stop this ?

["Wilkinson, Alex" <alex.wilkinson@xxxxxxxxxxxxxxxxxxx>]

Hi all,

I have the following folder-hook:

   folder-hook . \
               "set sort=reverse-threads ;\
                set sort_aux=last-date-received ;\
                push '<collapse-all>' ;\
                set index_format='%3N %4C %Z %{%b %d} %-15.15F (%4c) %?M?%M> 
?%s' ;\
                set display_filter='t-prot -acelmtS -Mmutt --spass'"

As well as this I have the following defined:

   set collapse_unread=yes

My problem:

   My INBOX will be open all day within a terminal as per usual and as soon as a
   new message for a particular thread arrives the thread un-collapses.

Is it possible to stop threads un-collaping as new mail arrives ?

 -aW

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