Context Menuのサブメニューへの移動
from Context Menu
サブメニューを開いたときと移動
https://www.smashingmagazine.com/2023/08/better-context-menus-safe-triangles/
http://classicshell.net/forum/viewtopic.php?f=13&t=347
Building like it's 1984: A comprehensive guide to creating intuitive context menus - Height
https://scrapbox.io/files/64d844a1dba3b6001c6a9234.mp4
https://gyazo.com/c53f7acd3fd0db58cdef3c7c71f3e648 https://medium.com/@nielsmanders/the-context-menu-safety-triangle-411c75065374
Chrome Dev Toolsがコレに対応していないUIだった
https://gyazo.com/b8e6d5e5c46bfc110afbf9ef39414865