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If I select a high-activity group I haven't read before (such as
gmane.linux.kernel which I guess is the mailing list and has hundreds
thousands posts) pan soon stops working/responding. I can no longer
select any other group, nor any menu item, and if I cover or minimize
pan and return later, it no longer even redraws its screen. Today this
has gone one for about six hours, which just to show one screen of
posts, it shouldn't take this long! I don't know why it'd have to
prepare to show all posts from years ago because I probably won't look
that far back. Pan even stops responding like this if I mark that I've
read all articles in the high-activity group and come back later,
perhaps just to see the top page of articles.