<off-topic>
> On Windows XP, they are replaced with a long black rectangle...
I also get those with the Quartz backend builds (GTK+/Quartz 3.6.2, gtkmm3 3.6.0, gdl3 3.6.2, glib2 2.34.3) - the same for the background of the thumbnail preview in the file dialogs.
Interestingly wit the same builds, the rulers are ok with the Unico theme engine, but black with Adwaita, and stock (i.e. no) theme engine.
</off-topic>
<off-topic>
> On Windows XP, they are replaced with a long black rectangle...
I also get those with the Quartz backend builds (GTK+/Quartz 3.6.2, gtkmm3 3.6.0, gdl3 3.6.2, glib2 2.34.3) - the same for the background of the thumbnail preview in the file dialogs.
Interestingly wit the same builds, the rulers are ok with the Unico theme engine, but black with Adwaita, and stock (i.e. no) theme engine.
</off-topic>