diff --git a/src/content-scripts/github.ts b/src/content-scripts/github.ts
new file mode 100644
index 00000000..33a87eb3
--- /dev/null
+++ b/src/content-scripts/github.ts
@@ -0,0 +1,35 @@
+import {
+  getGithubUsername,
+  isGithubProfilePage,
+  isGithubPullRequestPage,
+} from "../utils/urlMatchers";
+import { isOpenSaucedUser } from "../utils/fetchOpenSaucedApiData";
+import injectViewOnOpenSauced from "../utils/dom-utils/viewOnOpenSauced";
+import injectInviteToOpenSauced from "../utils/dom-utils/inviteToOpenSauced";
+import { prefersDarkMode } from "../utils/colorPreference";
+import injectAddPRToHighlightsButton from "../utils/dom-utils/addPRToHighlights";
+import domUpdateWatch from "../utils/dom-utils/domUpdateWatcher";
+import { isLoggedIn } from "../utils/checkAuthentication";
+
+const processGithubPage = async () => {
+  if (prefersDarkMode(document.cookie)) {
+    document.documentElement.classList.add("dark");
+  }
+
+  if (isGithubPullRequestPage(window.location.href)) {
+    setTimeout(injectAddPRToHighlightsButton, 10);
+  } else if (isGithubProfilePage(window.location.href)) {
+    const username = getGithubUsername(window.location.href);
+
+    if (!username) return;
+    if (await isOpenSaucedUser(username)) {
+      injectViewOnOpenSauced(username);
+    } else {
+      injectInviteToOpenSauced(username);
+    }
+  }
+
+  domUpdateWatch(processGithubPage);
+};
+
+void processGithubPage();
diff --git a/src/utils/dom-utils/domUpdateWatcher.ts b/src/utils/dom-utils/domUpdateWatcher.ts
new file mode 100644
index 00000000..9849eb9d
--- /dev/null
+++ b/src/utils/dom-utils/domUpdateWatcher.ts
@@ -0,0 +1,21 @@
+const domUpdateWatch = (callback: () => void) => {
+  const oldLocation = document.location.href;
+  const observer = new MutationObserver(
+    (_: unknown, observer: MutationObserver) => {
+      const newLocation = document.location.href;
+
+      if (oldLocation === newLocation || document.readyState !== "complete") {
+        return;
+      }
+      observer.disconnect();
+      setTimeout(callback, 20);
+    },
+  );
+
+  observer.observe(document.body, {
+    childList: true,
+    subtree: true,
+  });
+};
+
+export default domUpdateWatch;
diff --git a/src/worker/background.ts b/src/worker/background.ts
index 82033f53..a953bd53 100644
--- a/src/worker/background.ts
+++ b/src/worker/background.ts
@@ -1,12 +1,6 @@
 import { checkAuthentication } from "../utils/checkAuthentication";
 import { SUPABASE_AUTH_COOKIE_NAME, OPEN_SAUCED_INSIGHTS_DOMAIN } from "../constants";
 
-chrome.tabs.onUpdated.addListener((tabId, changeInfo) => {
-  if (changeInfo.url?.includes("github.com")) {
-    void chrome.tabs.sendMessage(tabId, { message: "GITHUB_URL_CHANGED" });
-  }
-});
-
 chrome.cookies.onChanged.addListener(changeInfo => {
     if (
       changeInfo.cookie.name === SUPABASE_AUTH_COOKIE_NAME ||