Is there a way to test the performance of a DOM element on a page?

[vivi]

Hello!

The tool webpagetest provides an option "-m, --dom <element>: DOM element to record for sub-measurement" when run the test command. After applying this option, I could not find where to find the performance for a particular DOM element.

May I know is there a way to test the time (CPU + network) spent on a DOM element (including the time on the children elements enclosed by the particular DOM element)?

Thanks in advance!!

Regards,
Vivi

[vivi]

Anyone can help to solve my concern?
Thanks!!

[pmeenan]

I don't think that is supported anymore (at least until a low-overhead way to implement it is figured out). The old way would poll the page DOM waiting for the element to show up but on complex pages the polling could add quite a bit of overhead and influence the results.