Broken XML editor icons (rev >= 10768, GTK_ICON_SIZE_SMALL_TOOLBAR)

Reproduced in Inskcape 0.48+devel r10955 on Mac OS X Leopard (GTK+ 2.24.4) and OS X Lion (GTK+ 2.24.8) - inkscape launched with default new preferences - if I force small toolbar icons via custom gtkrc file (gtk-toolbar-icon-size):

from ~/.gtkrc-2.0.mine:
# toolbar icon size (force small icons)
# fails with >= r10768 (XML Editor)
#gtk-toolbar-icon-size = 2

The (downscaled) icons are loaded and displayed when the dialog is closed and opened a second time within the current session.

The change was introduced with r10768:
Replace deprecated GtkToolbar API
<https://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/revision/10768>

Not reproduced with
- default gtkrc settings (no user gtkrc file, or no gtk-toolbar-icon-size in the settings file ), or
- explicitly setting 'gtk-toolbar-icon-size' to 3 (GTK_ICON_SIZE_LARGE_TOOLBAR)

Related:
<http://developer.gnome.org/gtk/2.24/gtk-Themeable-Stock-Images.html#GtkIconSize>
<http://developer.gnome.org/gtk/2.24/GtkSettings.html#GtkSettings--gtk-toolbar-icon-size>

Inkscape's gtkrc file installed on Windows does define a small toolbar icon size:
    gtk-toolbar-icon-size = small-toolbar

<https://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/view/head:/build.xml#L721>

Confirmed on Windows 7.
First time opening the XML Editor, the icons are broken.
But second time opening, the icons are ok.

Could this be related to/solved by Inkscape "pre-caching" some icons ?

Still affecting Inkscape 11649 on Windows XP.
Weirdly, the Delete attribute icon (on the right toolbar) is shown correctly while the left toolbar's icons (except the GTK stock icons) are broken. They're all created with the same kind of code.

Not reproduced on Crunchbang Waldorf, Inkscape trunk revision 13220.
The icons show correctly with the size forced in the .gtkrc-2.0.mine.

Still fails on Windows XP.

Not reproduced on Windows XP, with the experimental GTK3 devlibs (gtk-3.8.1, gtkmm-3.8.0).

Reproduced on Windows XP, official devlibs (gtk-2.24.10, gtkmm-2.24.2).
Setting gtk-toolbar-icon-size = 3 or removing it in "share\themes\MS-Windows\gtk-2.0\gtkrc" fixes the issue, but the large icon looks a bit too large IMHO.

@~suv - does Inkscape use the large icons when removing the gtkrc file on OS-X? With Crunchbang, removing it makes the icon show with a medium size. It's a bit weird since they are hard-coded to be large in the xml tree code.

> does Inkscape use the large icons when removing the gtkrc file on OS-X?

AFAIU this is unrelated to the platform - it depends on the gtkrc settings in the system gtkrc (and whether that exists at all), and on whatever the global gtk theme might mandate, and possibly on overriding user settings. MacPorts for example does not install a system-wide (system = MacPorts prefix) gtkrc file, and locally I do not have a settings daemon set up either (can't use that for packaging, or do not want to).

Yes, if no gtkrc is used at all (neither user nor theme nor system), the icons are found and rendered the first time the dialog is displayed, and they render at button size (24x24) - about the same size as the original SVG source.

Personally, I prefer smaller icons: if the system settings, or the theme or the user settings ask for small toolbar icons, Inkscape should adhere to that in all GUI widgets where icons / images are used for toolbar buttons.

In the newest stable release (Inkscape 0.91, 64bit Version, tested on Windows 7) this problem is even worse than it was before (at least I'm noticing it for the first time):
- When a button with a missing icon is disabled at the time when the XML editor is opened (e.g. when no object is selected) the icon is grayed out.
- When the button is enabled subsequently (e.g. by selecting an object) the icons STAYS grayed out.
- This means without hovering the button there is NO way to recognize whether the button is disabled or not.

This should therefore probably be fixed sooner rather than later!

Known workarounds (0.91, lp:inkscape/0.92.x):
a) close and reopen XML Editor in the current session
b) check 'Pre-render named icons' in 'Edit > Preferences > System' and relaunch inkscape

Maybe we could activate the 'Pre-render named icons' option by default?

Also affects the Fill and Stroke dialog (color picker icon), see duplicate Bug #1298743.

Still exists in Inkscape 0.92.3 (2405546, 2018-03-11) on Windows 7.
Using 'Pre-render named icons' workaround causes some icons to be rendered blurred.

Still exists in Inkscape 0.92.4 (5da689c313, 2019-01-14) on Windows 10.