bug#42039: 27.0.91; (posn-x-y (posn-at-point)) inconsistent with display-line-numbers-mode

[Eli Zaretskii]

> Cc: 42039@debbugs.gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Thu, 25 Jun 2020 21:35:59 +0300
> 
> 2. Put a display string on it that (important!) ends with a newline:
> 
> (overlay-put o 'display "abc\ndef\n")
> 
> 3. Eval
> 
> (car (posn-x-y (posn-at-point (overlay-start o))))
> 
> It will evaluate to 0 even if display-line-numbers-mode is enabled.

So this _is_ triggered only by display strings.  Thanks.