From efc8f22f6c583b7c4f358d23e1740ae0807b783e Mon Sep 17 00:00:00 2001 From: Marcus Summers Date: Thu, 9 Apr 2026 15:40:17 -0400 Subject: [PATCH] wiki: add curl_cffi impersonation fix for yt-dlp 429 errors YouTube rate-limits non-browser clients. Installing curl_cffi enables TLS fingerprint impersonation, fixing HTTP 429 on subtitle downloads. Co-Authored-By: Claude Opus 4.6 (1M context) --- .../yt-dlp-fedora-js-challenge.md | 20 +++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/05-troubleshooting/yt-dlp-fedora-js-challenge.md b/05-troubleshooting/yt-dlp-fedora-js-challenge.md index f4fec65..a9f89a4 100644 --- a/05-troubleshooting/yt-dlp-fedora-js-challenge.md +++ b/05-troubleshooting/yt-dlp-fedora-js-challenge.md @@ -121,6 +121,26 @@ yt-dlp --list-formats --remote-components ejs:github \ https://www.youtube.com/watch?v=VIDEO_ID ``` +### HTTP 429 Too Many Requests + Impersonation Warning + +Downloads or subtitle fetches fail with: + +``` +WARNING: The extractor specified to use impersonation for this download, +but no impersonate target is available. +ERROR: Unable to download video subtitles for 'en-en-US': HTTP Error 429: Too Many Requests +``` + +**Cause:** yt-dlp needs `curl_cffi` to impersonate a real browser's TLS fingerprint. Without it, YouTube detects the non-browser client and rate-limits with 429s. Subtitle downloads are usually the first to fail. + +**Fix:** + +```bash +pip3 install --upgrade yt-dlp curl_cffi +``` + +Once `curl_cffi` is installed, yt-dlp automatically uses browser impersonation and the 429s stop. No config changes needed. + ### SABR-Only Streaming Warning Some videos may show: