i dont know what girl you're referring to.
but i finally found the video. https://twitter.com/CGTNOfficial/status/1179758001248489477

this shit is really hard to find.
here's more random vids https://www.reddit.com/r/Sino/comments/dh7189/helpful_list_of_hong_kong_rioter_violence/?utm_source=amp&utm_medium=&utm_content=post_body
https://www.reddit.com/r/Sino/comments/dvah42/a_collection_of_hk_rioter_atrocities/

summary of events
reddit.com/r/Sino/wiki/faq/hong-kong-taiwan/summer-2019-protests