https://www.w3.org/standards/history/user-timing-2/
User Timing Level 2 publication history | Standards | W3C
The World Wide Web Consortium (W3C) is an international community where Member organizations, a full-time staff, and the public work together to develop Web...
user timinglevel 2publicationhistorystandards
https://triple-underscore.github.io/user-timing-ja.html
User Timing — （日本語訳）
user timing
https://caniuse.com/?search=ciu/user-timing
"ciu/user-timing" | Can I use... Support tables for HTML5, CSS3, etc
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