From 56dd49aaed6c49402dcc88e6005594a2e4d3ef2c Mon Sep 17 00:00:00 2001
From: Christopher Willis-Ford <7019101+cwillisf@users.noreply.github.com>
Date: Tue, 16 Aug 2022 23:42:55 -0700
Subject: [PATCH] fix(extensions): try harder to avoid Scratch Link init in
 non-browser environments

Prior to this change, the Scratch Link init would fail in JSDOM. That means it fails in the
scratch-gui integration tests, so that's no good...
---
 src/engine/runtime.js | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/engine/runtime.js b/src/engine/runtime.js
index 10e2d3b7..d79337ca 100644
--- a/src/engine/runtime.js
+++ b/src/engine/runtime.js
@@ -1444,8 +1444,17 @@ class Runtime extends EventEmitter {
      */
     _initScratchLink () {
         /* global globalThis */
-        // Check if we're actually in a browser
-        if (globalThis.document && document.getElementById) {
+        // Check that we're actually in a real browser, not Node.js or JSDOM, and we have a valid-looking origin.
+        if (globalThis.document &&
+            globalThis.document.getElementById &&
+            globalThis.origin &&
+            globalThis.origin !== 'null' &&
+            globalThis.navigator &&
+            globalThis.navigator.userAgent &&
+            globalThis.navigator.userAgent.includes &&
+            !globalThis.navigator.userAgent.includes('Node.js') &&
+            !globalThis.navigator.userAgent.includes('jsdom')
+        ) {
             // Create a script tag for the Scratch Link browser extension, unless one already exists
             const scriptElement = document.getElementById('scratch-link-extension-script');
             if (!scriptElement) {