diff --git a/.gitignore b/.gitignore
index 5205c64..0614f9f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@ node_modules/
 .DS_Store
 *.swp
 
-content_scripts/dist/*.js
\ No newline at end of file
+content_scripts/dist/*.js
+web-ext-artifacts/
diff --git a/README.md b/README.md
index b1685ef..0d0e772 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 Web API Manager
 ===
 
+
 Overview
 ---
 This extension allows users to selectively allow different hosts on the web
@@ -9,6 +10,7 @@ security and privacy sensitive web users to limit the attack surface presented
 to websites, and to limit websites to the functionality they actually need
 to carry out user-serving purposes.
 
+
 Background
 ---
 Web browsers gain staggering numbers of new features, without their users
diff --git a/background_scripts/background.js b/background_scripts/background.js
index ae840ca..b0b7b2f 100644
--- a/background_scripts/background.js
+++ b/background_scripts/background.js
@@ -1,8 +1,9 @@
 /*jslint es6: true*/
-/*global chrome, browser, window, URI*/
+/*global window*/
 (function () {
+    "use strict";
 
-    const {packingLib, standards, storageLib} = window.WEB_API_MANAGER;
+    const {packingLib, standards, storageLib, domainMatcherLib} = window.WEB_API_MANAGER;
     const rootObject = window.browser || window.chrome;
     const defaultKey = "(default)";
 
@@ -11,6 +12,9 @@
     // that should be blocked on matching domains.
     let domainRules;
 
+    // The extension depends on this fetch happening before the DOM on any
+    // pages is loaded.  The Chrome and Firefox docs *do not* promise this,
+    // but in testing this is always the case.
     storageLib.get(function (loadedDomainRules) {
         domainRules = loadedDomainRules;
     });
@@ -18,7 +22,7 @@
     // Manage the state of the browser activity, by displaying the number
     // of origins / frames
     const updateBrowserActionBadge = function (activeInfo) {
-        const {tabId, windowId} = activeInfo;
+        const tabId = activeInfo.tabId;
         rootObject.tabs.executeScript(
             tabId,
             {
@@ -50,39 +54,8 @@
     rootObject.tabs.onActivated.addListener(updateBrowserActionBadge);
     rootObject.windows.onFocusChanged.addListener(updateBrowserActionBadge);
 
-    // Inject the blocking settings for each visited domain / frame.
-    const extractHostFromUrl = function (url) {
-        const uri = URI(url);
-        return uri.hostname();
-    };
-
-    const matchingUrlReduceFunction = function (domain, prev, next) {
-        if (prev) {
-            return prev;
-        }
-
-        const domainRegex = new RegExp(next);
-        if (domainRegex.test(domain)) {
-            return next;
-        }
-
-        return prev;
-    };
-
-    const whichDomainRuleMatches = function (hostName) {
-        // of the URL being requested.
-        const matchingUrlReduceFunctionBound = matchingUrlReduceFunction.bind(undefined, hostName);
-        const matchingPattern = Object
-            .keys(domainRules)
-            .filter((aRule) => aRule !== defaultKey)
-            .sort()
-            .reduce(matchingUrlReduceFunctionBound, undefined);
-
-        return matchingPattern || defaultKey;
-    };
-
     // Listen for updates to the domain rules from the config page.
-    rootObject.runtime.onMessage.addListener(function (request, sender, sendResponse) {
+    rootObject.runtime.onMessage.addListener(function (request, ignore, sendResponse) {
         const [label, data] = request;
         if (label === "rulesUpdate") {
             domainRules = data;
@@ -90,12 +63,16 @@
         }
 
         if (label === "rulesForDomains") {
-            const ruleForDomain = data.map(whichDomainRuleMatches);
-            const mapping = {};
-            for (let i = 0; i < ruleForDomain.length; i += 1) {
-                mapping[data[i]] = ruleForDomain[i];
-            }
-            sendResponse(mapping);
+
+            const matchHostNameBound = domainMatcherLib.matchHostName.bind(undefined, Object.keys(domainRules));
+            const rulesForDomains = data.map(matchHostNameBound);
+            const domainToRuleMapping = {};
+
+            data.forEach(function (aHostName, index) {
+                domainToRuleMapping[aHostName] = rulesForDomains[index] || defaultKey;
+            });
+
+            sendResponse(domainToRuleMapping);
             return;
         }
     });
@@ -106,15 +83,15 @@
     };
     const requestOptions = ["blocking", "responseHeaders"];
 
-    chrome.webRequest.onHeadersReceived.addListener(function (details) {
+    // Inject the blocking settings for each visited domain / frame.
+    rootObject.webRequest.onHeadersReceived.addListener(function (details) {
 
         const url = details.url;
-        const hostName = extractHostFromUrl(url);
 
         // Decide which set of blocking rules to use, depending on the host
         // of the URL being requested.
-        const matchingDomainKey = whichDomainRuleMatches(hostName);
-        const standardsToBlock = domainRules[matchingDomainKey];
+        const matchingDomainRule = domainMatcherLib.matchUrl(Object.keys(domainRules), url);
+        const standardsToBlock = domainRules[matchingDomainRule || defaultKey];
 
         const options = Object.keys(standards);
         const packedValues = packingLib.pack(options, standardsToBlock);
@@ -129,4 +106,4 @@
         };
 
     }, requestFilter, requestOptions);
-}());
\ No newline at end of file
+}());
diff --git a/config/index.html b/config/index.html
index 2ceffb5..20f2e0e 100644
--- a/config/index.html
+++ b/config/index.html
@@ -34,9 +34,9 @@
             </div>
         </section>
         <script src="../lib/init.js"></script>
-        <script src="../lib/storage.js"></script>
         <script src="../content_scripts/dist/defaults.js"></script>
         <script src="../content_scripts/dist/standards.js"></script>
+        <script src="../lib/storage.js"></script>        
         <script src="js/lib/vue.js"></script>
         <script src="js/state.js"></script>
         <script src="js/components/domain-rules.vue.js"></script>
diff --git a/config/js/components/domain-rules.vue.js b/config/js/components/domain-rules.vue.js
index 7875c97..83e688a 100644
--- a/config/js/components/domain-rules.vue.js
+++ b/config/js/components/domain-rules.vue.js
@@ -1,5 +1,5 @@
-/*jslint es6: true*/
-/*global window, browser, Vue*/
+/*jslint es6: true, this: true*/
+/*global window, Vue*/
 (function () {
     "use strict";
 
@@ -65,6 +65,6 @@
             isDefault: function (domainName) {
                 return domainName === "(default)";
             }
-        },
+        }
     });
 }());
\ No newline at end of file
diff --git a/config/js/components/web-api-standards.vue.js b/config/js/components/web-api-standards.vue.js
index acc78d9..0a0e9a8 100644
--- a/config/js/components/web-api-standards.vue.js
+++ b/config/js/components/web-api-standards.vue.js
@@ -1,6 +1,7 @@
-/*jslint es6: true*/
-/*global window, browser, Vue*/
+/*jslint es6: true, this: true*/
+/*global window, Vue*/
 (function () {
+    "use strict";
 
     const standardsDefaults = window.WEB_API_MANAGER.defaults;
 
diff --git a/config/js/config.js b/config/js/config.js
index 79f694d..4f86cfb 100644
--- a/config/js/config.js
+++ b/config/js/config.js
@@ -6,25 +6,15 @@
     const rootObject = (window.browser || window.chrome);
     const doc = window.document;
     const standards = window.WEB_API_MANAGER.standards;
-    const defaultConservativeRules = window.WEB_API_MANAGER.defaults.conservative;
     const {storageLib, stateLib} = window.WEB_API_MANAGER;
     const defaultDomain = "(default)";
 
     const state = stateLib.generateStateObject(defaultDomain, standards);
 
-    const onSettingsLoaded = function (settingsResults) {
-
-        let loadedDomainRules;
-
-        if (Object.keys(settingsResults).length !== 0) {
-            loadedDomainRules = settingsResults;
-        } else {
-            loadedDomainRules = Object.create(null);
-            loadedDomainRules[defaultDomain] = defaultConservativeRules;
-        }
+    const onSettingsLoaded = function (loadedDomainRules) {
 
         state.setDomainRules(loadedDomainRules);
-        
+
         const vm = new Vue({
             el: doc.body,
             data: state
diff --git a/config/js/state.js b/config/js/state.js
index d8da92b..8dfba14 100644
--- a/config/js/state.js
+++ b/config/js/state.js
@@ -1,6 +1,7 @@
-/*jslint es6: true*/
+/*jslint es6: true, this: true*/
 /*global window, browser, Vue*/
 (function () {
+    "use strict";
 
     window.WEB_API_MANAGER.stateLib = {};
 
@@ -12,27 +13,27 @@
             domainRules: {},
             domainNames: [],
             selectedStandards: [],
-    
+
             setDomainRules: function (newDomainRules) {
                 this.domainRules = newDomainRules;
                 this.domainNames = Object.keys(newDomainRules);
                 this.selectedStandards = this.domainRules[this.selectedDomain];
             },
-    
+
             setSelectedDomain: function (newDomain) {
                 this.selectedDomain = newDomain;
                 this.selectedStandards = this.domainRules[newDomain];
             },
-    
+
             setSelectedStandards: function (selectedStandards) {
                 this.selectedStandards = selectedStandards;
                 this.domainRules[this.selectedDomain] = selectedStandards;
             },
-    
+
             deleteDomainRule: function (domainToDelete) {
                 delete this.domainRules[domainToDelete];
                 this.domainNames = Object.keys(this.domainRules);
-    
+
                 // If we're deleted the domain thats currently selected, then
                 // select the default domain.
                 if (this.selectedDomain === domainToDelete) {
diff --git a/lib/domainmatcher.js b/lib/domainmatcher.js
new file mode 100644
index 0000000..5e5986d
--- /dev/null
+++ b/lib/domainmatcher.js
@@ -0,0 +1,46 @@
+/*jslint es6: true*/
+/*global window*/
+(function () {
+    "use strict";
+    const defaultKey = "(default)";
+
+    const extractHostNameFromUrl = function (url) {
+        const uri = window.URI(url);
+        return uri.hostname();
+    };
+
+    const matchingUrlReduceFunction = function (hostName, prev, next) {
+        if (prev) {
+            return prev;
+        }
+
+        const domainRegex = new RegExp(next);
+        if (domainRegex.test(hostName)) {
+            return next;
+        }
+
+        return prev;
+    };
+
+    const matchHostName = function (domainRegExes, hostName) {
+        // of the URL being requested.
+        const matchingUrlReduceFunctionBound = matchingUrlReduceFunction.bind(undefined, hostName);
+        const matchingPattern = domainRegExes
+            .filter((aRule) => aRule !== defaultKey)
+            .sort()
+            .reduce(matchingUrlReduceFunctionBound, undefined);
+
+        return matchingPattern || undefined;
+    };
+
+    const matchUrl = function (domainRegExes, url) {
+        const hostName = extractHostNameFromUrl(url);
+        return matchHostName(domainRegExes, hostName);
+    };
+
+    window.WEB_API_MANAGER.domainMatcherLib = {
+        matchHostName,
+        matchUrl
+    };
+
+}());
\ No newline at end of file
diff --git a/lib/init.js b/lib/init.js
index 8585f2b..1e772b3 100644
--- a/lib/init.js
+++ b/lib/init.js
@@ -1,3 +1,7 @@
+/*global window*/
 // Initial content script for the Web API manager extension, that creates
 // the "namespace" we'll use for all the content scripts in the extension.
-window.WEB_API_MANAGER = {};
\ No newline at end of file
+(function () {
+    "use strict";
+    window.WEB_API_MANAGER = {};
+}());
diff --git a/lib/pack.js b/lib/pack.js
index 2504eeb..ec580c6 100644
--- a/lib/pack.js
+++ b/lib/pack.js
@@ -1,8 +1,9 @@
-/*jslint es6: true*/
+/*jslint es6: true, for: true, bitwise: true*/
 /*global window*/
 (function () {
     "use strict";
 
+    const {btoa, atob} = window;
     const bucketSize = 8;
 
     const bufferToBase64 = function (buf) {
@@ -16,7 +17,7 @@
         const binstr = atob(base64);
         const buf = new Uint8Array(binstr.length);
         Array.prototype.forEach.call(binstr, function (ch, i) {
-          buf[i] = ch.charCodeAt(0);
+            buf[i] = ch.charCodeAt(0);
         });
         return buf;
     };
@@ -47,11 +48,13 @@
         const binnedOptions = options.reduce(binToBucketSizeFunc, []);
         const bitFields = new Uint8Array(numBuckets);
 
-        for (let i = 0; i < numBuckets; i += 1) {
+        let i, j;
+
+        for (i = 0; i < numBuckets; i += 1) {
             let bitfield = 0;
             let currentBucket = binnedOptions[i];
 
-            for (let j = 0; j < currentBucket.length; j += 1) {
+            for (j = 0; j < currentBucket.length; j += 1) {
 
                 let currentOption = currentBucket[j];
                 if (selected.indexOf(currentOption) !== -1) {
@@ -68,7 +71,6 @@
 
     const unpack = function (options, data) {
 
-        const numBuckets = Math.ceil(options.length / bucketSize);
         const binToBucketSizeFunc = binOptionsReduceFunction.bind(undefined, bucketSize);
         options.sort();
 
@@ -77,11 +79,13 @@
 
         const result = [];
 
-        for (let i = 0; i < bitFields.length; i += 1) {
+        let i, j;
+
+        for (i = 0; i < bitFields.length; i += 1) {
             let currentBitField = bitFields[i];
             let currentOptionsBin = binnedOptions[i];
 
-            for (let j = 0; j < bucketSize; j += 1) {
+            for (j = 0; j < bucketSize; j += 1) {
                 if (currentBitField & (1 << j)) {
                     let currentOption = currentOptionsBin[j];
                     result.push(currentOption);
@@ -93,6 +97,7 @@
     };
 
     window.WEB_API_MANAGER.packingLib = {
-        pack, unpack
+        pack,
+        unpack
     };
 }());
\ No newline at end of file
diff --git a/lib/storage.js b/lib/storage.js
index 3ffbd87..b8e93d7 100644
--- a/lib/storage.js
+++ b/lib/storage.js
@@ -3,13 +3,25 @@
 (function () {
     "use strict";
 
-    const browserObj = window.browser || window.chrome;
+    const rootObject = window.browser || window.chrome;
+    const defaultConservativeRules = window.WEB_API_MANAGER.defaults.conservative;
     const webApiManagerKeySettingsKey = "webApiManagerDomainRules";
-    const storageObject = browserObj.storage;
+    const storageObject = rootObject.storage;
 
     const get = function (callback) {
         storageObject.local.get(webApiManagerKeySettingsKey, function (results) {
-            callback(results && results[webApiManagerKeySettingsKey]);
+
+            let loadedDomainRules = results && results[webApiManagerKeySettingsKey];
+
+            // If there are no currently saved domain rules, then create
+            // a stubbed out one, using the conservative blocking rule set.
+            if (!loadedDomainRules || Object.keys(loadedDomainRules).length === 0) {
+                loadedDomainRules = {
+                    "(default)": defaultConservativeRules
+                };
+            }
+
+            callback(loadedDomainRules);
         });
     };
 
diff --git a/manifest.json b/manifest.json
index 84ee897..a3026d7 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,7 +1,7 @@
 {
   "manifest_version": 2,
   "name": "WebAPI Manager",
-  "version": "0.5",
+  "version": "0.7",
   "description": "Improves browser security by restricting page access to parts of the Web API.",
   "icons": {
     "48": "images/uic-48.png",
@@ -37,20 +37,21 @@
     "lib/init.js",
     "lib/js.cookie.js",
     "lib/storage.js",
-    "lib/URI.js"
+    "lib/URI.js",
+    "content_scripts/dist/defaults.js"
   ],
   "background": {
     "scripts": [
       "lib/init.js",
       "lib/pack.js",
-      "lib/storage.js",
       "lib/URI.js",
       "content_scripts/dist/standards.js",
+      "content_scripts/dist/defaults.js",
+      "lib/storage.js",
       "background_scripts/background.js"
     ]
   },
   "options_ui": {
-    "page": "config/index.html",
-    "chrome_style": true
+    "page": "config/index.html"
   }
 }
diff --git a/popup/js/popup.js b/popup/js/popup.js
index 27cfc4c..a0473ae 100644
--- a/popup/js/popup.js
+++ b/popup/js/popup.js
@@ -1,8 +1,11 @@
 /*jslint es6: true*/
 /*global window*/
 (function () {
+    "use strict";
+
     const rootObject = window.browser || window.chrome;
-    const configureButton = window.document.getElementById("config-page-link");
+    const doc = window.document;
+    const configureButton = doc.getElementById("config-page-link");
 
     configureButton.addEventListener("click", function (event) {
         rootObject.runtime.openOptionsPage();
@@ -21,26 +24,26 @@
             const message = ["rulesForDomains", uniqueDomains];
             rootObject.runtime.sendMessage(message, function (response) {
 
-                const listGroupElm = document.querySelector("ul.list-group");
+                const listGroupElm = doc.querySelector("ul.list-group");
                 const domainNames = Object.keys(response);
 
                 domainNames.forEach(function (aDomain) {
                     const domainRule = response[aDomain];
-                    
-                    const liElm = document.createElement("li");
+
+                    const liElm = doc.createElement("li");
                     liElm.className = "list-group-item";
                     if (domainRule !== "(default)") {
                         liElm.className += " list-group-item-success";
                     }
 
-                    const spanElm = document.createElement("span");
+                    const spanElm = doc.createElement("span");
                     spanElm.className = "badge";
 
-                    const badgeText = document.createTextNode(domainRule);
+                    const badgeText = doc.createTextNode(domainRule);
                     spanElm.appendChild(badgeText);
                     liElm.appendChild(spanElm);
 
-                    const textElm = document.createTextNode(aDomain);
+                    const textElm = doc.createTextNode(aDomain);
                     liElm.appendChild(textElm);
                     listGroupElm.appendChild(liElm);
                 });