diff --git a/common/content/commands.js b/common/content/commands.js
index fb334ba3..e0d2e9c9 100644
--- a/common/content/commands.js
+++ b/common/content/commands.js
@@ -1049,18 +1049,16 @@ var Commands = Module("commands", {
 
     validName: Class.memoize(function () RegExp("^" + this.nameRegexp.source + "$")),
 
-    CommandMatch: Struct("match", "spec", "prespace", "count", "cmd", "bang", "space", "args"),
-
     commandRegexp: Class.memoize(function () util.regexp(<![CDATA[
             ^
-            (
-                ([:\s]*)
-                ( (?:\d+ | %)? )
-                ( (?:<name> | !)? )
-                (!?)
-                (\s*)
+            (?P<spec>
+                (?P<prespace> [:\s]*)
+                (?P<count>    (?:\d+ | %)? )
+                (?P<cmd>      (?:<name> | !)? )
+                (?P<bang>     !?)
+                (?P<space>    \s*)
             )
-            (
+            (?P<args>
                 (?:. | \n)*?
             )?
             $
@@ -1229,7 +1227,6 @@ var Commands = Module("commands", {
             let match = commands.commandRegexp.exec(args.commandString);
             if (!match)
                 return;
-            match = commands.CommandMatch.apply(null, match);
 
             context.advance(match.prespace.length + match.count.length);
             if (!(match.bang || match.space)) {
diff --git a/common/content/dactyl.js b/common/content/dactyl.js
index 13fd68e0..596ec803 100644
--- a/common/content/dactyl.js
+++ b/common/content/dactyl.js
@@ -51,7 +51,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
         autocommands.trigger("Leave", {});
     },
 
-    observe: {
+    observers: {
         "dactyl-cleanup": function () {
             let modules = dactyl.modules;
 
diff --git a/common/content/marks.js b/common/content/marks.js
index 2f2d87a0..a0762960 100644
--- a/common/content/marks.js
+++ b/common/content/marks.js
@@ -126,7 +126,7 @@ var Marks = Module("marks", {
                     let items = array(util.range(0, sh.count));
 
                     let a = items.slice(0, sh.index).reverse();
-                    let b = items.slice(sh.index, sh.count);
+                    let b = items.slice(sh.index);
                     a.length = b.length = Math.max(a.length, b.length);
                     items = array(a).zip(b).flatten().compact();
 
diff --git a/common/content/statusline.js b/common/content/statusline.js
index 888336a7..0d623666 100644
--- a/common/content/statusline.js
+++ b/common/content/statusline.js
@@ -38,13 +38,13 @@ var StatusLine = Module("statusline", {
         let prepend = <e4x xmlns={XUL} xmlns:dactyl={NS}>
             <statusbar id="status-bar" highlight="StatusLine">
                 <!-- insertbefore="dactyl.statusBefore;" insertafter="dactyl.statusAfter;" -->
-                <hbox key="container" hidden="false" align="center" flex="1">
-                    <stack orient="horizontal" align="stretch"      flex="1" class="dactyl-container" highlight="CmdLine StatusCmdLine">
-                        <hbox                                                class="dactyl-container" highlight="CmdLine StatusCmdLine">
-                            <label key="mode"          crop="end"            class="plain" collapsed="true"/>
-                            <stack flex="1"                                  class="dactyl-container" highlight="CmdLine StatusCmdLine">
-                                <textbox key="url"     crop="end"   flex="1" class="plain dactyl-status-field-url" readonly="true"/>
-                                <textbox key="message" crop="end"   flex="1" class="plain"            highlight="Normal StatusNormal" readonly="true"/>
+                <hbox key="container" hidden="false" align="center"  flex="1">
+                    <stack orient="horizontal"       align="stretch" flex="1" highlight="CmdLine StatusCmdLine" class="dactyl-container">
+                        <hbox                                                 highlight="CmdLine StatusCmdLine" class="dactyl-container">
+                            <label key="mode"          crop="end"                                               class="plain" collapsed="true"/>
+                            <stack                                   flex="1" highlight="CmdLine StatusCmdLine" class="dactyl-container">
+                                <textbox key="url"     crop="end"    flex="1"                                   class="plain dactyl-status-field-url" readonly="true"/>
+                                <textbox key="message" crop="end"    flex="1" highlight="Normal StatusNormal"   class="plain"                         readonly="true"/>
                             </stack>
                         </hbox>
 
diff --git a/common/modules/highlight.jsm b/common/modules/highlight.jsm
index 00ee36cc..8d5bf05f 100644
--- a/common/modules/highlight.jsm
+++ b/common/modules/highlight.jsm
@@ -212,11 +212,11 @@ var Highlights = Module("Highlight", {
     sheetRegexp: util.regexp(<![CDATA[
         ^\s*
         !? \*?
-             ( (?:[^;\s]|\s[^;\s])+ )
-        (?:; ( (?:[^;\s]|\s[^;\s])+ )? )?
-        (?:; ( (?:[^;\s]|\s[^;\s])+ )? )?
-        (?:; ( (?:[^;\s]|\s[^;\s])+ )? )?
-        \s*  (.*)
+             (?P<group>    (?:[^;\s]|\s[^;\s])+ )
+        (?:; (?P<selector> (?:[^;\s]|\s[^;\s])+ )? )?
+        (?:; (?P<sites>    (?:[^;\s]|\s[^;\s])+ )? )?
+        (?:; (?P<extends>  (?:[^;\s]|\s[^;\s])+ )? )?
+        \s*  (?P<css>      .*)
         $
     ]]>),
 
diff --git a/common/modules/io.jsm b/common/modules/io.jsm
index 4651eca1..1cf0b637 100644
--- a/common/modules/io.jsm
+++ b/common/modules/io.jsm
@@ -929,22 +929,25 @@ unlet s:cpo_save
         completion.addUrlCompleter("f", "Local files", function (context, full) {
             let match = util.regexp(<![CDATA[
                 ^
-                (
-                    ((chrome|resource):\/\/)
+                (?P<prefix>
+                    (?P<proto>
+                        (?P<scheme> chrome|resource)
+                        :\/\/
+                    )
                     [^\/]*
                 )
-                (\/[^\/]*)?
+                (?P<path> \/[^\/]* )?
                 $
             ]]>).exec(context.filter);
             if (match) {
-                if (!match[4]) {
-                    context.key = match[2];
-                    context.advance(match[2].length);
-                    context.generate = function () util.chromePackages.map(function (p) [p, match[2] + p + "/"]);
+                if (!match.path) {
+                    context.key = match.proto;
+                    context.advance(match.proto.length);
+                    context.generate = function () util.chromePackages.map(function (p) [p, match.proto + p + "/"]);
                 }
-                else if (match[3] === "chrome") {
-                    context.key = match[1];
-                    context.advance(match[1].length + 1);
+                else if (match.scheme === "chrome") {
+                    context.key = match.prefix;
+                    context.advance(match.prefix.length + 1);
                     context.generate = function () iter({
                         content: "Chrome content",
                         locale: "Locale-specific content",
@@ -952,7 +955,7 @@ unlet s:cpo_save
                     });
                 }
             }
-            if (!match || match[3] === "resource" && match[4])
+            if (!match || match.scheme === "resource" && match.path)
                 if (/^(\.{0,2}|~)\/|^file:/.test(context.filter) || util.getFile(context.filter) || io.isJarURL(context.filter))
                     completion.file(context, full);
         });
diff --git a/common/modules/prefs.jsm b/common/modules/prefs.jsm
index 4e2039c3..0264ee2a 100644
--- a/common/modules/prefs.jsm
+++ b/common/modules/prefs.jsm
@@ -33,7 +33,7 @@ var Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference])
         this.branch.removeObserver("", this);
     },
 
-    observe: {
+    observers: {
         "nsPref:changed": function (subject, data) {
             let observers = this._observers[data];
             if (observers) {
diff --git a/common/modules/sanitizer.jsm b/common/modules/sanitizer.jsm
index 1b5c68c5..d211d288 100644
--- a/common/modules/sanitizer.jsm
+++ b/common/modules/sanitizer.jsm
@@ -228,7 +228,7 @@ var Sanitizer = Module("sanitizer", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakRef
                 Class.objectGlobal(params.action));
     },
 
-    observe: {
+    observers: {
         "browser:purge-domain-data": function (subject, host) {
             storage.fireEvent("sanitize", "domain", host);
             // If we're sanitizing, our own sanitization functions will already
diff --git a/common/modules/styles.jsm b/common/modules/styles.jsm
index ecc5b29c..acc6ae5a 100644
--- a/common/modules/styles.jsm
+++ b/common/modules/styles.jsm
@@ -214,6 +214,7 @@ var Hive = Class("Hive", {
     },
 });
 
+try {
 /**
  * Manages named and unnamed user style sheets, which apply to both
  * chrome and content pages.
@@ -330,16 +331,15 @@ var Styles = Module("Styles", {
         let match, i = 0;
         while ((!match || match[0]) && (match = Styles.propertyPattern.exec(str)))
             if (always && !i++ || match[0] && match[3])
-                yield this.Property.fromArray(match);
+                yield match;
     },
 
-    Property: Struct("whole", "preSpace", "name", "value", "postSpace"),
     propertyPattern: util.regexp(<![CDATA[
             (?:
-                (<space>*)
-                ([-a-z]*)
+                (?P<preSpace> <space>*)
+                (?P<name> [-a-z]*)
                 (?:
-                    <space>* : \s* (
+                    <space>* : \s* (?P<value>
                         (?:
                             [-\w]
                             (?:
@@ -355,7 +355,7 @@ var Styles = Module("Styles", {
                     )
                 )?
             )
-            (<space>* (?: ; | $) )
+            (?P<postSpace> <space>* (?: ; | $) )
         ]]>, "gi",
         {
             space: /(?: \s | \/\* .*? \*\/ )/,
@@ -550,6 +550,6 @@ var Styles = Module("Styles", {
 
 endModule();
 
-// catch(e){dump(e.fileName+":"+e.lineNumber+": "+e+"\n" + e.stack);}
+} catch(e){dump(e.fileName+":"+e.lineNumber+": "+e+"\n" + e.stack);}
 
 // vim: set fdm=marker sw=4 ts=4 et ft=javascript:
diff --git a/common/modules/util.jsm b/common/modules/util.jsm
index 9bc373e7..bd47cd9f 100644
--- a/common/modules/util.jsm
+++ b/common/modules/util.jsm
@@ -93,11 +93,11 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
      * @param {object} obj
      */
     addObserver: function (obj) {
-        let observers = obj._observe || obj.observe;
-        obj._observe = observers;
+        if (!obj.observers)
+            obj.observers = obj.observe;
 
         function register(meth) {
-            for (let target in set(["dactyl-cleanup-modules", "quit-application"].concat(Object.keys(observers))))
+            for (let target in set(["dactyl-cleanup-modules", "quit-application"].concat(Object.keys(obj.observers))))
                 try {
                     services.observer[meth](obj, target, true);
                 }
@@ -109,8 +109,8 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
                 try {
                     if (target == "quit-application" || target == "dactyl-cleanup-modules")
                         register("removeObserver");
-                    if (observers[target])
-                        observers[target].call(obj, subject, data);
+                    if (obj.observers[target])
+                        obj.observers[target].call(obj, subject, data);
                 }
                 catch (e) {
                     util.reportError(e);
@@ -948,7 +948,7 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
         return color ? string : [s for each (s in string)].join("");
     },
 
-    observe: {
+    observers: {
         "dactyl-cleanup-modules": function () {
             defineModule.loadLog.push("dactyl: util: observe: dactyl-cleanup-modules");
 
@@ -1219,14 +1219,31 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
     regexp: update(function (expr, flags, tokens) {
         if (isinstance(expr, ["RegExp"]))
             expr = expr.source;
+
         if (tokens)
             expr = String.replace(expr, /<(\w+)>/g, function (m, n1) set.has(tokens, n1) ? tokens[n1].source || tokens[n1] : m);
+
         expr = String.replace(expr, /\/\/[^\n]*|\/\*[^]*?\*\//gm, "")
                      .replace(/\s+/g, "");
-        return update(RegExp(expr, flags), {
+
+        if (/\(\?P</.test(expr)) {
+            let groups = ["wholeMatch"];
+            expr = expr.replace(/((?:[^[(\\]|\\.|\[(?:[^\]]|\\.)*\])*)\((?:\?P<([^>]+)>|(\?))?/gy,
+                function (m0, m1, m2, m3) {
+                    if (!m3)
+                        groups.push(m2 || "-group-" + groups.length);
+                    return m1 + "(" + (m3 || "");
+                });
+            var struct = Struct.apply(null, groups);
+        }
+
+        let res = update(RegExp(expr, flags), {
             closure: Class.Property(Object.getOwnPropertyDescriptor(Class.prototype, "closure")),
             dactylPropertyNames: ["exec", "match", "test", "toSource", "toString", "global", "ignoreCase", "lastIndex", "multiLine", "source", "sticky"]
         });
+        if (struct)
+            update(res, { exec: function exec() struct.fromArray(exec.superapply(this, arguments)) });
+        return res;
     }, {
         /**
          * Escapes Regular Expression special characters in *str*.