--- a/gfx/2d/DrawTargetCairo.cpp
+++ b/gfx/2d/DrawTargetCairo.cpp
@@ -1285,16 +1285,17 @@ DrawTargetCairo::FillGlyphs(ScaledFont *
 
   if (!IsValid()) {
     gfxDebug() << "FillGlyphs bad surface " << cairo_surface_status(cairo_get_group_target(mContext));
     return;
   }
 
   if (!aFont) {
     gfxDevCrash(LogReason::InvalidFont) << "Invalid scaled font";
+    return;
   }
 
   AutoPrepareForDrawing prep(this, mContext);
   AutoClearDeviceOffset clear(aPattern);
 
   ScaledFontBase* scaledFont = static_cast<ScaledFontBase*>(aFont);
   cairo_set_scaled_font(mContext, scaledFont->GetCairoScaledFont());