diff --git a/gfx/thebes/gfxPlatformMac.cpp b/gfx/thebes/gfxPlatformMac.cpp
index d62e5cb1b..3b4301d3c 100644
--- a/gfx/thebes/gfxPlatformMac.cpp
+++ b/gfx/thebes/gfxPlatformMac.cpp
@@ -303,6 +303,10 @@ gfxPlatformMac::IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags)
 
                     HTTP_OR_HTTPS_SUBDIR("www.adac.de", "/assets/font/milo-");
 
+                    HTTP_OR_HTTPS_SUBDIR("www.heise.de", "/sso/fonts/SourceSansPro-");
+
+                    HTTP_OR_HTTPS_SUBDIR("www.vetmed.fu-berlin.de", "/assets/default2/NexusSansWeb-P");
+
                     // Check hostname and subpatterns (TenFourFox issue 477).
                     HOST_AND_KEY("www.latimes.com", "/fonts/KisFBDisplay-");
                     HOST_AND_KEY("www.nerdwallet.com", "Gotham-Book--critical");