[networking] Ignore invalid proxies in env (#7704)

Authored by: coletdjnz

1 files changed, 7 insertions, 3 deletions

diff --git a/yt_dlp/networking/common.py b/yt_dlp/networking/common.py
index ab26a0628..3164df49b 100644
--- a/yt_dlp/networking/common.py
+++ b/yt_dlp/networking/common.py
@@ -262,9 +262,13 @@ class RequestHandler(abc.ABC):
                 # Skip proxy scheme checks
                 continue
 
-            # Scheme-less proxies are not supported
-            if urllib.request._parse_proxy(proxy_url)[0] is None:
-                raise UnsupportedRequest(f'Proxy "{proxy_url}" missing scheme')
+            try:
+                if urllib.request._parse_proxy(proxy_url)[0] is None:
+                    # Scheme-less proxies are not supported
+                    raise UnsupportedRequest(f'Proxy "{proxy_url}" missing scheme')
+            except ValueError as e:
+                # parse_proxy may raise on some invalid proxy urls such as "/a/b/c"
+                raise UnsupportedRequest(f'Invalid proxy url "{proxy_url}": {e}')
 
             scheme = urllib.parse.urlparse(proxy_url).scheme.lower()
             if scheme not in self._SUPPORTED_PROXY_SCHEMES: