This wasn't a MINIMO problem, but rather a static build problem. NPODB

extensions/spatialnavigation/src/Makefile.in

@@ -95,7 +95,7 @@ CPPSRCS     = nsSpatialNavigation.cpp \
 # defined.  We do not use this class anywhere in this
 # extension.
 
-ifndef MINIMO
+ifndef BUILD_STATIC_LIBS
 DEFINES += -D_IMPL_NS_GFX
 CPPSRCS += nsRect.cpp nsFont.cpp
 endif