youtube-dl 2021.12.17 Core [postprocessor/ffmpeg] Show ffmpeg output on error (#22680, #29336) Extractors [youtube] Update signature function patterns (#30363, #30366) [peertube] Only call description endpoint if necessary (#29383) [periscope] Pass referer to HLS requests (#29419) [liveleak] Remove extractor (#17625, #24222, #29331) [pornhub] Add support for pornhubthbh7ap3u.onion [pornhub] Detect