如何在PC上旋轉youtube影片

如何在PC上旋轉youtube影片:
How to rotate youtube videos on PC:

1.首先安裝Tampermonkey (First install Tampermonkey) 
https://tinyurl.com/n23yerc

2. 安裝 install YouTube Rotate 90°
https://tinyurl.com/ychathfs

3. 按下按鈕旋轉影片 (Press the button to rotate the video)