Severity: wishlist
Tags: patch

A user on Libera.Chat recently reported that the track module's mode
line segment reacts to messages from members of `erc-fools' when the
option `erc-fool-highlight-type' is set to something other than `all'.
Those offending variants, including the default of `nick', all arrange
for applying `erc-fool-face' to only a portion of an inserted message.

To reproduce from -Q:

  1. Connect to a server and join a channel containing "somenick"
  2. M-x erc-add-fool RET somenick RET
  3. Switch away from the channel buffer
  4. Notice the mode line reacts when "somenick" speaks

This behavior is present in all versions at least as far back as ERC 5.3
(Emacs 27). In addition to removing `erc-fool-face' from
`erc-track-faces-priority-list', setting

  (setopt erc-fool-highlight-type 'all
          erc-track-priority-faces-only 'all)

is also needed to silence the mode line segment effectively. (Omitting
either does not.)

There are many ways to go about addressing this. One lazy possibility is
shown in the attached patch, which has `track' ignore all invisible
messages, though this requires users to also do

  (setopt erc-text-matched-hook '(erc-hide-fools))

or similar to obtain the desired effect. On the plus side, users will no
longer have to fiddle with any of the other options mentioned above.


In GNU Emacs 31.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
 3.24.49, cairo version 1.18.2) of 2025-08-03 built on localhost
Repository revision: c935b68bed174386f46dec6be525a23397a4b5f8
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12401008
System Description: Fedora Linux 42 (Workstation Edition)

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