Icon for global preferences

[houz]

The global preferences currently use "preferences-system" as its icon. According to https://bugs.kde.org/show_bug.cgi?id=359248 that is not intended to be used for things like this and "gtk-preferences" is to be used instead. The same wrong icon is used in GTK2 based builds, the provided patch probably won't work there though.

I would ask you to apply the provided patch as at least the breeze icon theme (which is default for KDE users) has a terrible icon for the currently used one which breaks the look and usability of Inkscape in several ways.

Thanks for considering this.

[Mc (mc...)]

pushed to .92 r15145 and trunk r15202

[su_v (suv-lp)]

AFAIU 'gtk-preferences' is a deprecated stock icon name and should not be used anymore. It is not provided out-of-the-box by the default icon theme for GTK3 (Adwaita).

«The “Preferences” item and icon.

Deprecated since version 3.10: Use named icon “preferences-system” or the label “_Preferences”.»

https://developer.gnome.org/gtk3/stable/gtk3-Stock-Items.html#GTK-STOCK-PREFERENCES:CAPS
https://lazka.github.io/pgi-docs/#Gtk-3.0/constants.html#Gtk.STOCK_PREFERENCES
https://git.gnome.org/browse/gtk+/tree/testsuite/gtk/check-icon-names.c?h=gtk-3-22#n51

It is not listed in the icon naming spec either:
https://specifications.freedesktop.org/icon-naming-spec/latest/
https://developer.gnome.org/icon-naming-spec/

Some icon themes may include it (as symbolic link, or as separate icon), others only provide it if the tool 'icon-naming-utils' from the tango project («A script for creating a symlink mapping for deprecated icon names to the new Icon Naming Specification names, for desktop icon themes.») is used to create a symbolic link (to 'preferences-desktop'):

Snippet from icon-naming-utils/legacy-icon-mapping.xml:

 <icon name="preferences-desktop">
     <link>gnome-control-center</link>
     <link>gnome-settings</link>
     <link>gtk-preferences</link>
     <link>redhat-preferences</link>
     <link>kcontrol</link>
     <link>xfce4-settings</link>
 </icon>

Note that current stable inkscape 0.92.x won't expose either name as missing icon because the icons.svg file in stable includes a copy of the GTK2 stock item (added for bug #1269698), with id references by both icon names ('preferences-system', 'gtk-preferences').

With current GTK3 trunk builds however, the icon with the id 'gtk-preferences' may be shown as missing (it is not provided by Adwaita itself, the default icon theme for GTK3), as happens with current builds on Windows based on inkscape-devlibs64, and with Eduard Braun's MSYS2 builds (which use up-to-date upstream versions of the dependencies). If the commit based on this report is reverted (r15202), the icon is shown as expected (and as provided by Adwaita) with GTK3-based trunk builds.

Proposing to revert the change in GTK3-based trunk, or to at least consult with upstream GTK+ about future usage/support of icon names from deprecated stock items, and any upstream recommendations for GTK3-based apps to achieve optimal cross-platform and cross-desktop support.

[su_v (suv-lp)]

For a follow-up wrt missing 'gtk-preferences' icon with GTK3 trunk builds on Windows, see:
https://bugs.launchpad.net/inkscape/+bug/1659336/comments/5

Even with the issue of hicolor's index.theme solved (either use none, or the default one), the deprecated 'gtk-preferences' icon seems a limiting choice for GTK3 builds - the deprecated fallback stock icon (no custom icon theme is installed which would provide it) does not render as symbolic icon if requested via theme stylesheet:

* {
    -gtk-icon-style: symbolic;
}

This theme setting works as expected with the named icon 'preferences-system' (provided by default Adwaita icon theme).