--- a/python/lldbutils/README.txt
+++ b/python/lldbutils/README.txt
@@ -120,17 +120,19 @@ In lldb terminology, type summaries are 
 when using the "expression" command (or its familiar-to-gdb-users "p" alias),
 and synthetic children are fake member variables or array elements also
 added by custom rules.
 
 For objects that do have synthetic children defined for them, like nsTArray,
 the "expr -R -- EXPR" command can be used to show its actual member variables.
 
 
-* nsAString, nsACString
+* nsAString, nsACString,
+  nsFixedString, nsFixedCString,
+  nsAutoString, nsAutoCString
 
   Strings have a type summary that shows the actual string.
 
   (lldb) frame info
   frame #0: 0x000000010400cfea XUL`nsCSSParser::ParseProperty(this=0x00007fff5fbf5248, aPropID=eCSSProperty_margin_top, aPropValue=0x00007fff5fbf53f8, aSheetURI=0x0000000115ae8c00, aBaseURI=0x0000000115ae8c00, aSheetPrincipal=0x000000010ff9e040, aDeclaration=0x00000001826fd580, aChanged=0x00007fff5fbf5247, aIsImportant=false, aIsSVGMode=false) + 74 at nsCSSParser.cpp:12851
   (lldb) p aPropValue
   (const nsAString_internal) $16 = u"-25px"