Repository: yt-dlp
Issue: CeskaTelevize broken
Labels: site-bug

### DO NOT REMOVE OR SKIP THE ISSUE TEMPLATE

- [X] I understand that I will be **blocked** if I *intentionally* remove or skip any mandatory\* field

### Checklist

- [X] I'm reporting that a **supported** site is broken
- [X] I've verified that I'm running yt-dlp version **2023.03.04** ([update instructions](https://github.com/yt-dlp/yt-dlp#update)) or later (specify commit)
- [X] I've checked that all provided URLs are playable in a browser with the same IP and same login details
- [X] I've checked that all URLs and arguments with special characters are [properly quoted or escaped](https://github.com/yt-dlp/yt-dlp/wiki/FAQ#video-url-contains-an-ampersand--and-im-getting-some-strange-output-1-2839-or-v-is-not-recognized-as-an-internal-or-external-command)
- [X] I've searched [known issues](https://github.com/yt-dlp/yt-dlp/issues/3766) and the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues **including closed ones**. DO NOT post duplicates
- [X] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)
- [X] I've read about [sharing account credentials](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#are-you-willing-to-share-account-details-if-needed) and I'm willing to share it if required

### Region

Should be available everywhere

### Provide a description that is worded well enough to be understood

Looks like something has been changed in this web today.

### Provide verbose output that clearly demonstrates the problem

- [X] Run **your** yt-dlp command with **-vU** flag added (`yt-dlp -vU <your command line>`)
- [X] If using API, add `'verbose': True` to `YoutubeDL` params instead
- [X] Copy the WHOLE output (starting with `[debug] Command-line config`) and insert it below

### Complete Verbose Output

```shell
[debug] Command-line config: ['-vU', 'https://www.ceskatelevize.cz/porady/10078945173-kouzlo-afriky/205552110600001/']
[debug] User config "C:\Users\jiri\yt-dlp.conf": ['--user-agent', 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.71 Safari/537.36', '--no-check-certificate', '--sponsorblock-remove', 'all', '-o', 'D:\\Downloads\\yt-dlp\\%(autonumber)03d_%(title)s.%(ext)s', '--no-mtime', '--format', 'bestvideo[ext=mp4][height<=1080][fps<=30]+bestaudio[ext=m4a]/best[ext=mp4][height<=1080][fps<=30]/best[height<=1080][fps<=30]/best', '--merge-output-format', 'mkv', '--ffmpeg-location', 'C:\\Apps\\ffmpeg\\bin\\ffmpeg.exe', '--all-subs', '-i', '--compat-options', 'multistreams', '--remux-video', 'mkv', '--add-header', 'accept-language: cs,fi;q=0.9,en-US;q=0.8,en;q=0.7,en-GB;q=0.6', '--add-header', 'sec-ch-ua: "Chromium";v="94", "Google Chrome";v="94", ";Not A Brand";v="99"', '--add-header', 'sec-ch-ua-arch: "x86"', '--add-header', 'sec-ch-ua-bitness: "64"', '--add-header', 'sec-ch-ua-full-version: "94.0.4606.71"', '--add-header', 'sec-ch-ua-mobile: ?0', '--add-header', 'sec-ch-ua-model: ""', '--add-header', 'sec-ch-ua-platform: "Windows"', '--add-header', 'sec-ch-ua-platform-version: "10.0.0"', '--add-header', 'sec-fetch-dest: document', '--add-header', 'sec-fetch-mode: navigate', '--add-header', 'sec-fetch-site: none', '--add-header', 'sec-fetch-user: ?1', '--add-header', 'service-worker-navigation-preload: true', '--add-header', 'upgrade-insecure-requests: 1', '--add-header', 'alt-svc: h3=":443"; ma=2592000,h3-29=":443"; ma=2592000,h3-T051=":443"; ma=2592000,h3-Q050=":443"; ma=2592000,h3-Q046=":443"; ma=2592000,h3-Q043=":443"; ma=2592000,quic=":443"; ma=2592000; v="46,43"', '--add-header', 'cache-control: no-cache, no-store, max-age=0, must-revalidate']
[debug] Encodings: locale UTF-8, fs utf-8, pref UTF-8, out utf-8, error utf-8, screen utf-8
[debug] yt-dlp version stable@2023.03.04 [392389b7d] (win_exe)
[debug] Compatibility options: multistreams
[debug] Python 3.8.10 (CPython AMD64 64bit) - Windows-10-10.0.19045-SP0 (OpenSSL 1.1.1k  25 Mar 2021)
[debug] exe versions: ffmpeg 4.4-full_build-www.gyan.dev (setts), ffprobe 4.4-full_build-www.gyan.dev, phantomjs 2.1.1

[debug] Optional libraries: Cryptodome-3.17, brotli-1.0.9, certifi-2022.12.07, mutagen-1.46.0, sqlite3-2.6.0, websockets-10.4
[debug] Proxy map: {}
[debug] Loaded 1786 extractors
[debug] Fetching release info: https://api.github.com/repos/yt-dlp/yt-dlp/releases/latest
Available version: stable@2023.03.04, Current version: stable@2023.03.04
Current Build Hash: 5590c57bd0433ed239a2deaaf92e2ad6f37fe50f53664c821575cafe106a9421
yt-dlp is up to date (stable@2023.03.04)
[CeskaTelevize] Extracting URL: https://www.ceskatelevize.cz/porady/10078945173-kouzlo-afriky/205552110600001/
[CeskaTelevize] 205552110600001: Downloading webpage
[CeskaTelevize] 205552110600001: Getting IFRAME hash
ERROR: [CeskaTelevize] 205552110600001: Unable to download webpage: HTTP Error 404: Not Found (caused by <HTTPError 404: 'Not Found'>); please report this issue on  https://github.com/yt-dlp/yt-dlp/issues?q= , filling out the appropriate issue template. Confirm you are on the latest version using  yt-dlp -U
  File "yt_dlp\extractor\common.py", line 694, in extract
  File "yt_dlp\extractor\ceskatelevize.py", line 122, in _real_extract
  File "yt_dlp\extractor\common.py", line 1097, in _download_webpage
  File "yt_dlp\extractor\common.py", line 1048, in download_content
  File "yt_dlp\extractor\common.py", line 882, in _download_webpage_handle
  File "yt_dlp\extractor\common.py", line 839, in _request_webpage

  File "yt_dlp\extractor\common.py", line 821, in _request_webpage
  File "yt_dlp\YoutubeDL.py", line 3742, in urlopen
  File "urllib\request.py", line 531, in open
  File "urllib\request.py", line 640, in http_response
  File "urllib\request.py", line 569, in error
  File "urllib\request.py", line 502, in _call_chain
  File "urllib\request.py", line 649, in http_error_default
urllib.error.HTTPError: HTTP Error 404: Not Found
```