Is there a way to determine mapbox performance?

[nonoumasy]

For eg, I get conflicting reports on pages on my site. Some say they have issues, lag, etc while some don't see this issue on their end. Is there a way to measure performance programatically? On my end, I don't see any issues.

Sample page:
https://history-maps.com/story/Greek-Persian-Wars

[ChristopherLyon]

An add, how hardware dependant is the library really? I also see a lot of variation in performance for even simple maps and initial load time. Do we have any best practices for a SWR type cache load then re-validate? Would save 500-600ms of looking at a blank screen for a lot of users, especially in globe view with fog.