Browsertime can not collect all google core vital metrics such as LCP,CLS, TBT
tlqiao opened this issue · comments
Have you read the documentation?
- Yes, I've read the how to make a reproducable bug guide
- Yes, I've read the how to debug my script guide
URL
What are you trying to accomplish
Run the browsertime with cli and choose the safari as the browser, the performance result does not include LCP,CLS, TBT metrics. here is running command.
browsertime https://apple.com -n=1 --browser=safari
What browser did you use?
Safari Mac OS
How to reproduce
run the command browsertime https://apple.com -n=1 --browser=safari.Relevant log output
taoli@taolis-MacBook-Pro ~ % browsertime https://apple.com -n=1 --browser=safari
[2023-01-30 17:12:49] INFO: Running tests using Safari - 1 iteration(s)
[2023-01-30 17:12:50] INFO: Testing url https://apple.com iteration 1
[2023-01-30 17:13:17] INFO: https://apple.com TTFB: 0ms, FCP: 1.96s, DOMContentLoaded: 2.02s, Load: 14.06s
[2023-01-30 17:13:17] INFO: Wrote data to browsertime-results/apple.com/2023-01-30T171249+0800
As you can see, only can collect FCP metric, other metrics can not collect. why.
Hi @tlqiao Safari hasn't implemented any of those metrics, the only user experience metric in Safari so far is First Contentful paint (FCP). that the Wikimedia performance team paid for. The best way to try to fix that is to add an issue for WebKit (if it doesn't already exists) in https://bugs.webkit.org.
Best
Peter
Thanks for updating.