Enhanced internet connection checks by falling back to HTTPS protocol when HTTP (port 80) fails // Resolve #4980

platformio/http.py

@@ -190,10 +190,11 @@ class HTTPClient:
 @util.memoized(expire="10s")
 def _internet_on():
     timeout = 2
+    use_proxy = is_proxy_set()
     socket.setdefaulttimeout(timeout)
     for host in __check_internet_hosts__:
         try:
-            if is_proxy_set():
+            if use_proxy:
                 requests.get("http://%s" % host, allow_redirects=False, timeout=timeout)
                 return True
             # try to resolve `host` for both AF_INET and AF_INET6, and then try to connect
@@ -203,6 +204,15 @@ def _internet_on():
             return True
         except:  # pylint: disable=bare-except
             pass
+
+    # falling back to HTTPs, issue #4980
+    for host in __check_internet_hosts__:
+        try:
+            requests.get("https://%s" % host, allow_redirects=False, timeout=timeout)
+        except requests.exceptions.RequestException:
+            pass
+        return True
+
     return False