The "start-here" icon in g-i-t don't follow guidelines for GNOME foot
logo[1]:
"Elements such as outlines, reflections, drop shadows, etc. also
may not be added to it."
"The GNOME foot's fill color may be modified (preferably to
colors in the GNOME palette.) Patterns appropriate to the
subject matter of the subproject (e.g., a globe pattern for the
translation team) may be used to fill the GNOME foot logo."
This means that the "start-here" icons shouldn't add the light outline,
and the gradient used to fill it could be inopportune.
But we need both outline and gradient to make icon readable on screen:
the outline, particularly, is useful to distinguish the icon on dark
background (see [2]). So, we can't follow Tango guidelines to produce a
GNOME logo icon.
Could we propose an amendment to logo guidelines? It could be a good
topic for GUADEC.