bug#69463: 29.2; Isearch help icon has inconsistent size

[Sergio Callegari <sergio.callegari@gmail.com>]

Trying to look into the matter, I have found the file
`/usr/share/emacs/29.2/lisp/isearch.el.gz`, which I understand is the 
source of the code implementing the isearch functionality.

In this file, there is a portion of code that appears to be in charge of 
configuring the toolbar, starting in
`(defvar isearch-tool-bar-map ... )`

The portion setting the icon for help should be:
```
(define-key map [isearch-describe-mode]
       (list 'menu-item "Help" 'isearch-describe-mode
             :help "Get help for Isearch"
             :image '(isearch-tool-bar-image "help")))
```

However, if I try to evaluate `(isearch-tool-bar-image "help")` I get
`/usr/share/emacs/29.2/etc/images/help.xpm`

That is definitely a life buoy, but not the life buoy that is shown as 
the help icon when I press CTRL+s. In fact, it is the life buoy that I 
see in most emacs screenshots on the internet. Most important this one 
seems to have the right size.

So my system seems to disregard the default icons shipped with emacs and 
to look for something different. My wild guess is that this depends on 
gtk theming. My second wild guess is that because I am on KDE this 
theming is not configured at all and is wrong.

To provide more context, I am on an arch derived distro (Manjaro), with 
KDE. I use the breeze theme, that seems to have exactly that too big 
life buoy.

I need help on the following points:

- Why is that breeze icon being picked? Is there a way to force emacs to 
use its own icons? Theming would be nice, but done in this way, with a 
wild mixture of breeze icons and native emacs icons it is simply messy.

- Why is that breeze icon not scaled? All other applications on my 
system appear to scale their icons consistently.

Thanks!
Sergio

On 29/02/2024 18:42, Juri Linkov wrote:
>> When you press CTRL+s, I-search is activated, that provides a custom
>> toolbar with dedicated icons and lets one enter what to search in the
>> mode line.
>>
>> Unfortunately, in the toolbar there is a help icon, shaped as a life
>> buoy, that is too big or at least inconsistently big wrt the other icons.
>> As a consequence, when I-search is activated the emacs windows
>> becomes bigger to accomodate space for the taller toolbar.
>>
>> Not only having the window changing its size causes some inconvenience
>> because the text you are trying to focus on moves up and down. There is
>> a major problem if the emacs window is already vertically maximized
>> before you start searching. In fact, in this case there is no space for
>> the window to grow. As a consequence, the mode line goes out of the
>> screen and you cannot use it to search!
> 
> This behavior is system-dependent.  For example,
> I can't reproduce it on these configurations:
> 
> GNU Emacs 29.1.90 (build 1, x86_64-pc-linux-gnu,
> cairo version 1.16.0)
> 
> GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, X toolkit,
> cairo version 1.16.0, Xaw3d scroll bars)
> 
> GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20,
> cairo version 1.16.0)
> 
> Strange, the last is similar to your configuration:
> 
>> In GNU Emacs 29.2 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.40,
>> cairo version 1.18.0)