video_downloadhelper 视频下载 

https://addons.mozilla.org/zh-CN/firefox/addon/video-downloadhelper/

ruffle 将 Flash 重新带回网络

https://ruffle.rs/

https://ruffle.rs/downloads

https://addons.mozilla.org/zh-CN/firefox/addon/ruffle_rs/

https://microsoftedge.microsoft.com/addons/detail/ruffle-flash-emulator/pipjjbgofgieknlpefmcckdmgaaegban