Re: bug#41584: 26.3; org-indent-mode's line-prefix text property flickers near overlays

[Eli Zaretskii]

> From: Kévin Le Gouguec <kevin.legouguec@gmail.com>
> Date: Thu, 28 May 2020 21:54:09 +0200
> Cc: emacs-orgmode@gnu.org, Dmitry Gutov <dgutov@yandex.ru>
> 
> - emacs -Q
> - C-x C-f repro.org
> - M-x org-indent-mode
> - M-: (insert "* heading\ntext")
> - M-:
> (let ((ov (make-overlay (point-at-bol) (point-at-bol)))
>       (val (propertize " " 'display '((left-fringe right-triangle)))))
>   (overlay-put ov 'before-string val))
> - RET
> - a
> 
> When "a" is inserted, org-indent-mode's line-prefix disappears on the
> *previous* line ("text").  It remains gone as long as I type
> self-inserting characters, until
> 
> - I type certain commands, e.g. RET or C-j, or
> 
> - I insert a closing delimiter that makes
>   blink-paren-post-self-insert-function blink the corresponding opening
>   delimiter, e.g. ')' or ']'.
> 
> Then the line-prefix shows up again.

In fact, it's enough to type "M-x".  Which is a clear sign that some
redisplay optimization kicks in where it shouldn't.  And indeed,
setting inhibit-try-window-id non-nil solves the problem.

I will look into this when I have time, thanks for an easy reproducer.