Re: help-echo property disappearing

[Eli Zaretskii <eliz@gnu.org>]

> From: "Nicolas P. Rougier (inria)" <nicolas.rougier@inria.fr>
> Date: Fri, 15 Dec 2023 08:29:24 +0100
> 
> 
> I'm playing with the help-echo property and it keeps disappearing 
> for no obvious reason. I would like to confirm the behavior and to 
> know if this is the intended behavior. Here is a simple example:
> 
> (progn
>   (goto-char (point-min))
>   (insert (propertize "TEST"
>                       'another-property "Test message"
>                       'help-echo "Test message"))
>   (goto-char (point-min))
>   (kill-visual-line) (yank))
> 
> Before kill/yank, the string has both the `help-echo` and 
> `another-property` set, but the yanked string has only the 
> `another-property` set. This is in text-mode, using Emacs 29.1. I 
> also observed that in prog-modes, I cannot set the help-echo 
> property at all (with no warning).

This is the intended behavior, see yank-excluded-properties.