diff --git a/src/hb-common.cc b/src/hb-common.cc
index bd4cd88..0c13c7d 100644
--- a/src/hb-common.cc
+++ b/src/hb-common.cc
@@ -815,7 +815,7 @@
   }
 
   const char *p = *pp;
-  while (*pp < end && (**pp != ' ' && **pp != '=' && **pp != '['))
+  while (*pp < end && (**pp != ' ' && **pp != '=' && **pp != '[' && **pp != quote))
     (*pp)++;
 
   if (p == *pp || *pp - p > 4)