Subject: 26.3; next-error-highlight set to t doesn't seem semi-permanent

From: Howard Melman <[email-masked]>
Date: Sat, 28 Dec 2019 14:42:56 -0500

I tried this with emacs -Q on a mac using Gnu Emacs 26.3.

Using customize-variable I set next-error-highlight to t ("Semipermanent
highlighting") and saved that value for the current session.

I then ran M-x grep and got a *grep* buffer and moved through the errors
using n and p. The matches appeared in another window and were
highlighted but the highlighting disappeared after a short time (could
be the default value of 0.5 seconds) even if I didn't hit a key.

My understanding of next-error-highlight is when set to t, the
highlighting should remain until I enter another command. Yet 
it seems to disappear on it's own.

Howard

In GNU Emacs 26.3 (build 1, x86_64-apple-darwin18.2.0, NS appkit-1671.20 Version 10.14.3 (Build 18D109))
of 2019-09-02 built on builder10-14.porkrind.org
Windowing system distributor 'Apple', version 10.3.1671
Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Creating customization items...
Creating customization items ...done
Resetting customization items...done
Creating customization setup...done
To install your edits, invoke [State] and choose the Set operation
ls does not support --dired; see ‘dired-use-ls-dired’ for more details.
Grep finished with matches found
File local-variables error: (void-function python-black-on-save-mode)

Configured using:
'configure --with-ns '--enable-locallisppath=/Library/Application
Support/Emacs/${version}/site-lisp:/Library/Application
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Configured features:
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Important settings:
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Major mode: Python

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  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
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Load-path shadows:
None found.

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Memory information:
((conses 16 259054 13300)
(symbols 48 24850 2)
(miscs 40 179 325)
(strings 32 44096 2342)
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