Tags: patch Set summary line format to display line number. Something like this, (setq gnus-summary-line-format "%4P %U%R%z %-16&user-date; %(%[%4L:%*%-23,23f%]%) %B%s\n" This will display line number in the first column. Start Gnus and enter any group with few emails in it (better if there are threads in it). Invoke T-T (gnus-summary-toggle-threads) or any of the limiting functions like /-/ (gnus-summary-limit-to-subject). These calls invoke gnus-summary-prepare function. And every time gnus-summary-prepare is invoked it starts increamenting line-number from the previous max. The result is that, on each refresh the line number keep on increasing. And showing incorrect values. I have moved these two lines from gnus-summary-read-group-1 to gnus-summary-prepare function. (when (boundp 'gnus-pick-line-number) (setq gnus-pick-line-number 0)) This fixes the issue. Unless there are side-effects that I am unaware of. In GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.5, cairo version 1.16.0) of 2020-12-16 built on lt Repository revision: fda9a2bbfd3adcce046c03bee72ba848c61a3e29 Repository branch: master Windowing system distributor 'The X.Org Foundation', version 11.0.12004000 System Description: Debian GNU/Linux 10 (buster) Configured using: 'configure --prefix=/home/pankaj/.local'