diff --git a/src/background.ts b/src/background.ts
index bfb7b963..c1a9e8e0 100644
--- a/src/background.ts
+++ b/src/background.ts
@@ -1,6 +1,7 @@
 import * as CompileConfig from "../config.json";
 
 import Config from "./config";
+import { Registration } from "./types";
 // Make the config public for debugging purposes
 (<any> window).SB = Config;
 
@@ -90,7 +91,7 @@ chrome.runtime.onInstalled.addListener(function (object) {
  * 
  * @param {JSON} options 
  */
-function registerFirefoxContentScript(options) {
+function registerFirefoxContentScript(options: Registration) {
     const oldRegistration = contentScriptRegistrations[options.id];
     if (oldRegistration) oldRegistration.unregister();
 
diff --git a/src/types.ts b/src/types.ts
index bb1b0c6d..d7818e01 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -63,6 +63,21 @@ interface PreviewBarOption {
     opacity: string
 }
 
+
+interface Registration {
+    message: string,
+    id: string,
+    allFrames: boolean,
+    js: browser.extensionTypes.ExtensionFileOrCode[],
+    css: browser.extensionTypes.ExtensionFileOrCode[],
+    matches: string[]
+}
+
+interface BackgroundScriptContainer {
+    registerFirefoxContentScript: (opts: Registration) => void,
+    unregisterFirefoxContentScript: (id: string) => void
+}
+
 type VideoID = string;
 
 export {
@@ -74,5 +89,7 @@ export {
     SponsorTime,
     VideoID,
     SponsorHideType,
-    PreviewBarOption
-};
\ No newline at end of file
+    PreviewBarOption,
+    Registration,
+    BackgroundScriptContainer
+};
diff --git a/src/utils.ts b/src/utils.ts
index 6e4f2a28..149d99cf 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,12 +1,12 @@
 import Config from "./config";
-import { CategorySelection, SponsorTime, FetchResponse } from "./types";
+import { CategorySelection, SponsorTime, FetchResponse, BackgroundScriptContainer, Registration } from "./types";
 
 import * as CompileConfig from "../config.json";
 
 class Utils {
     
     // Contains functions needed from the background script
-    backgroundScriptContainer: any = null;
+    backgroundScriptContainer: BackgroundScriptContainer | null = null;
 
     // Used to add content scripts and CSS required
     js = [
@@ -19,7 +19,7 @@ class Utils {
         "popup.css"
     ];
 
-    constructor(backgroundScriptContainer?: any) {
+    constructor(backgroundScriptContainer?: BackgroundScriptContainer) {
         this.backgroundScriptContainer = backgroundScriptContainer;
     }
 
@@ -92,7 +92,7 @@ class Utils {
                 firefoxCSS.push({file});
             }
 
-            const registration = {
+            const registration: Registration = {
                 message: "registerContentScript",
                 id: "invidious",
                 allFrames: true,