1 files changed, 12 insertions, 0 deletions
diff --git a/src/lib/UA.js b/src/lib/UA.js
new file mode 100644
index 0000000..1a1771a
--- /dev/null
+++ b/src/lib/UA.js
@@ -0,0 +1,12 @@
+var UA = {
+  isMozilla: document.URL.startsWith("moz-"),
+}
+
+if (!UA.isMozilla) {
+  if (typeof chrome === "object" && !chrome.tabs && typeof exportFunction === "undefined") {
+    // content script shims
+    window.exportFunction = () => {};
+  }
+} else {
+  document.documentElement.classList.add("mozwebext");
+}