如何使用C#将facebook共享的youtube链接转换为实际的youtube链接？

我正在尝试将Facebook上的Youtube链接转换为原始的Youtube链接

但我找不到任何类似于此目的的代码

在facebook上发布时，我得到了这种格式的视频url

https://www.youtube.com/watch?v=https://m.facebook.com/story.php?story_fbid=137180674769618&id=744284273020098&refid=18&_ft_=qid.6890741645663138454%3Amf_story_key.778345062947352%3Agroup_id.744284273020098%3Atop_level_post_id.778345062947352%3Atl_objid.778345062947352%3Acontent_owner_id_new.100054330590900%3Apage_id.744284273020098%3Asrc.22%3Astory_location.6%3Astory_attachment_style.share%3Afilter.GroupStoriesByActivityEntQuery%3Atds_flgs.3%3Aott.AX89EZnntOWyt_cV%3Apage_insights.%7B%22744284273020098%22%3A%7B%22page_id%22%3A744284273020098%2C%22page_id_type%22%3A%22group%22%2C%22actor_id%22%3A100054330590900%2C%22dm%22%3A%7B%22isShare%22%3A1%2C%22originalPostOwnerID%22%3A0%7D%2C%22psn%22%3A%22EntGroupMallPostCreationStory%22%2C%22post_context%22%3A%7B%22object_fbtype%22%3A657%2C%22publish_time%22%3A1602049213%2C%22story_name%22%3A%22EntGroupMallPostCreationStory%22%2C%22story_fbid%22%3A%5B778345062947352%5D%7D%2C%22role%22%3A1%2C%22sl%22%3A6%7D%7D&__tn__=C-R

我需要找到的是最初发布的YouTube链接，如下所示

https://www.youtube.com/watch?v=xxxxxxxxxx

---

我应该从哪里开始实现这一目标？任何帮助都将不胜感激。

这不能是链接，因为这不是一个有效的链接。你确定上面的链接是正确的吗？我试过了，但不是我得到的。或者请解释更多关于如何获得该链接的信息。