Add checking for user agent to popup script

static/popup.js

@@ -1,5 +1,5 @@
 async function showNoChromiumPopup() {
-  if (localStorage.getItem("no-chromium-popup-shown") != "1") {
+  if (navigator.userAgent.includes("Chrome") && localStorage.getItem("no-chromium-popup-shown") != "1") {
 
     const divPage = document.createElement("div");
     const response = await fetch("https://no-chromium.org/popup/");