Working version

content.js

@@ -0,0 +1,45 @@
+const script = document.createElement('script');
+script.type = 'text/javascript';
+script.defer = false;
+script.async = false;
+script.src = chrome.runtime.getURL("inject.js");
+(document.head || document.documentElement).appendChild(script);
+
+//Reset variables at every page load in background.js
+if (window === window.parent){
+    chrome.runtime.sendMessage({type: "RESET"},null);
+}
+
+//Send PSSH into background.js
+document.addEventListener('pssh', (e) => {
+    chrome.runtime.sendMessage({
+        type: "PSSH",
+        text: e.detail
+    },null);
+});
+
+//Send Clearkey into background.js
+document.addEventListener('clearkey', (e) => {
+    chrome.runtime.sendMessage({
+        type: "CLEARKEY",
+        text: e.detail
+    },null);
+});
+
+//Fetch from original origin
+chrome.runtime.onMessage.addListener(
+    function (request, sender, sendResponse) {
+        if(request.type=="FETCH"){
+            let res = fetch(request.u, {
+                method: request.m,
+                headers: JSON.parse(request.h),
+                body: Uint8Array.from(atob(request.b), c => c.charCodeAt(0))
+            }).then((r)=>r.arrayBuffer()).then((r)=>{
+                sendResponse(
+                    btoa(String.fromCharCode(...new Uint8Array(r)))
+                );
+            })
+        }
+        return true
+    }
+);