diff --git a/data/options.css b/data/options.css
index c6bd61e..a2b6496 100644
--- a/data/options.css
+++ b/data/options.css
@@ -1,3 +1,21 @@
+setting[pref-name="rng"] {
+	border-bottom: 0px transparent none;
+	padding-top: 0.5em;
+}
+setting[pref-name="storePersistentRnd"]{
+	border-top: 0px transparent none;
+	border-bottom: 0px transparent none;
+}
+setting[pref-name="persistentRndStorage"]{
+	border-top: 0px transparent none;
+	border-bottom: 0px transparent none;
+	display: none;
+}
+setting[pref-name="clearPersistentRnd"]{
+	border-top: 0px transparent none;
+	border-bottom: 0px transparent none;
+}
+
 setting[pref-name="showNotifications"] {
 	border-bottom: 0px transparent none;
 	padding-top: 0.5em;
diff --git a/lib/main.js b/lib/main.js
index 7865b1f..875cc8f 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -39,18 +39,49 @@
 	});
 	
 	// persistent rng
-	const persistentRnd = Object.create(null);
+	var persistentRnd = Object.create(null);
+	try {
+		let storedData = JSON.parse(prefs.persistentRndStorage);
+		for (var domain in storedData){
+			var value = storedData[domain];
+			if (
+				Array.isArray(value) &&
+				value.length === 128 &&
+				value.every(function(value){return typeof value === "number" && value >= 0 && value < 256;})
+			){
+				persistentRnd[domain] = value;
+			}
+		}
+	}
+	catch(e){}
+	
 	processes.port.on("canvasBlocker-new-domain-rnd", function(process, data){
 		processes.port.emit("canvasBlocker-set-domain-rnd", data);
 		persistentRnd[data.domain] = data.rnd;
+		if (prefs.storePersistentRnd){
+			prefs.persistentRndStorage = JSON.stringify(persistentRnd);
+		}
 	});
-	processes.on("attach", function(process){
+	processes.forEvery(function(process){
 		if (process.isRemote){
-			for (var name in persistentRnd){
-				process.port.emit("canvasBlocker-set-domain-rnd", {domain: name, rnd: persistentRnd[name]});
+			for (var domain in persistentRnd){
+				process.port.emit("canvasBlocker-set-domain-rnd", {domain, rnd: persistentRnd[domain]});
 			}
 		}
 	});
+	preferences.on("storePersistentRnd", function(){
+		if (prefs.storePersistentRnd){
+			prefs.persistentRndStorage = JSON.stringify(persistentRnd);
+		}
+		else {
+			prefs.persistentRndStorage = "";
+		}
+	});
+	preferences.on("clearPersistentRnd", function(){
+		persistentRnd = Object.create(null);
+		prefs.persistentRndStorage = "";
+		processes.port.emit("canvasBlocker-clear-domain-rnd");
+	});
 	
 	// show release notes
 	var data = require("sdk/self").data;
diff --git a/lib/randomSupplies.js b/lib/randomSupplies.js
index b03dc82..575bf35 100644
--- a/lib/randomSupplies.js
+++ b/lib/randomSupplies.js
@@ -17,19 +17,23 @@
 		return window.location.host;
 	}
 	const getPersistentRnd = (function(){
+		var persistentRnd = Object.create(null);
+		
 		const {process} = require("sdk/remote/child");
 		process.port.on("canvasBlocker-set-domain-rnd", function(process, {domain, rnd}){
 			persistentRnd[domain] = new Uint8Array(rnd);
 		});
+		process.port.on("canvasBlocker-clear-domain-rnd", function(){
+			persistentRnd = Object.create(null);
+		});
 		
-		const persistentRnd = Object.create(null);
 		return function getPersistentRnd(window){
 			var domain = getDomain(window);
 			if (!persistentRnd[domain]){
 				// create the (sub-)domains random numbers if not existing
 				persistentRnd[domain] = new Uint8Array(128);
 				window.crypto.getRandomValues(persistentRnd[domain]);
-				process.port.emit("canvasBlocker-new-domain-rnd", {domain, rnd: persistentRnd[domain]});
+				process.port.emit("canvasBlocker-new-domain-rnd", {domain, rnd: Array.from(persistentRnd[domain])});
 			}
 			return persistentRnd[domain];
 		}
diff --git a/locale/de-DE.json b/locale/de-DE.json
index b064a10..ae3184d 100644
--- a/locale/de-DE.json
+++ b/locale/de-DE.json
@@ -31,6 +31,16 @@
 	"rng_options.persistent": "persistent",
 	"rng_options.non persistent": "nicht persistent",
 	"rng_title": "Zufallszahlengenerator",
+
+	"persistentRndStorage_title": "Persistenter Speicher",
+	"persistentRndStorage_description": "Speichert die Informationen für den persistenten Zufallszahlengenerator über einen Neustart hinweg.",
+	
+	"storePersistentRnd_title": "Persistente Daten speichern",
+	"storePersistentRnd_description": "Ob Daten für den persistenten Zufallszahlengenerator gespeichert werden sollen.",
+	
+	"clearPersistentRnd_title": "Persistenten Speicher leeren",
+	"clearPersistentRnd_description": "Löscht alle Daten für den persistenten Zufallszahlengenerator.",
+	"clearPersistentRnd_label": "Leeren",
 	
 	"disableNotifications": "Benachrichtigungen deaktivieren",
 	"displayCallingStack": "Aufrufestack anzeigen",
diff --git a/locale/en-US.json b/locale/en-US.json
index 667c3fd..d092321 100644
--- a/locale/en-US.json
+++ b/locale/en-US.json
@@ -29,8 +29,18 @@
 	
 	"rng_description": "",
 	"rng_options.persistent": "persistent",
-	"rng.non persistent": "non persistent",
+	"rng_options.non persistent": "non persistent",
 	"rng_title": "Random number generator",
+	
+	"persistentRndStorage_title": "Persistent storage",
+	"persistentRndStorage_description": "Stores the data for the persistent random number generator for usage after restart.",
+	
+	"storePersistentRnd_title": "Store persistent data",
+	"storePersistentRnd_description": "If data for the persistent random number generator should be stored.",
+	
+	"clearPersistentRnd_title": "Clear persistent random storage",
+	"clearPersistentRnd_description": "Deletes all data for the persistent random number generator.",
+	"clearPersistentRnd_label": "Clear",
 
 	"disableNotifications": "disable notifications",
 	"displayCallingStack": "display calling stack",
diff --git a/package.json b/package.json
index 445442a..879d9be 100644
--- a/package.json
+++ b/package.json
@@ -94,6 +94,24 @@
 				}
 			]
 		},
+		{
+			"name": "persistentRndStorage",
+			"title": "Persistent storage",
+			"type": "string",
+			"value": ""
+		},
+		{
+			"name": "storePersistentRnd",
+			"title": "Store persistent data",
+			"type": "bool",
+			"value": false
+		},
+		{
+			"name": "clearPersistentRnd",
+			"title": "Clear persistent random storage",
+			"type": "control",
+			"label": "Clear"
+		},
 		{
 			"name": "askOnlyOnce",
 			"title": "Ask only once",
diff --git a/releaseNotes.txt b/releaseNotes.txt
index 81d60b7..a1c3275 100644
--- a/releaseNotes.txt
+++ b/releaseNotes.txt
@@ -3,7 +3,7 @@ Version 0.3.7:
 		- 
 	
 	new features:
-		- 
+		- data for persistent random number generator can be stored
 	
 	fixes:
 		- fake at input was broken