diff --git a/common/modules/base.jsm b/common/modules/base.jsm
index e0f0eaad..105639d4 100644
--- a/common/modules/base.jsm
+++ b/common/modules/base.jsm
@@ -150,19 +150,24 @@ this.lazyRequire("services", ["services"]);
 this.lazyRequire("storage", ["File"]);
 this.lazyRequire("util", ["FailedAssertion", "util"]);
 
+literal.files = {};
+literal.locations = {};
 function literal(/* comment */) {
     let { caller } = Components.stack;
     while (caller && caller.language != 2)
         caller = caller.caller;
 
     let file = caller.filename.replace(/.* -> /, "");
-    let key = "literal:" + file + ":" + caller.line;
+    let key = "literal:" + file + ":" + caller.lineNumber;
+    if (Set.has(literal.locations, key))
+        return literal.locations[key];
 
-    let source = File.readURL(file);
+    let source = literal.files[file] || File.readURL(file);
+    literal.files[file] = source;
 
     let match = RegExp("(?:.*\\n){" + (caller.lineNumber - 1) + "}" +
                        ".*literal\\(/\\*([^]*?)\\*/\\)").exec(source);
-    return match[1];
+    return literal.locations[key] = match[1];
 
     // Later...
     return cache.get(key, function () {
diff --git a/common/modules/buffer.jsm b/common/modules/buffer.jsm
index 97b37b25..9ae00643 100644
--- a/common/modules/buffer.jsm
+++ b/common/modules/buffer.jsm
@@ -644,9 +644,10 @@ var Buffer = Module("Buffer", {
             }
 
         let link = DOM("link[href][rev=canonical], \
-                        link[href][rel=shortlink]", doc);
-        if (link.length)
-            return hashify(link.attr("href"));
+                        link[href][rel=shortlink]", doc)
+                       .attr("href");
+        if (link)
+            return hashify(link);
 
         return null;
     },
diff --git a/pentadactyl/install.rdf b/pentadactyl/install.rdf
index d7060288..18c945b8 100644
--- a/pentadactyl/install.rdf
+++ b/pentadactyl/install.rdf
@@ -31,7 +31,7 @@
         <em:targetApplication>
             <Description
                 em:id="{ec8030f7-c20a-464f-9b0e-13a3a9e97384}"
-                em:minVersion="24.0"
+                em:minVersion="22.0"
                 em:maxVersion="25.*"/>
         </em:targetApplication>
     </Description>