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Problem automating getting correct first input delay on mobile phones
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Description

I've been trying to automate to get the same problem as in T358380: The user is on a mobile phone, switch to desktop, click on the TOC and get high first input delays.

If I connect my phone to my desktop computer and inspect using devtools, I get the high "Input delay" on my interactions. I put a trace here:
https://trace.cafe/t/pE7T9jvEiH

However when I try to automate the same, doing the exact same steps and clicking on the TOC, I get the interactions but not the same Input delay. Using automation that is only 6 ms and not 100+. I tried clicking on different elements to make sure I mimic it correctly but no luck. Let me add trace with some clicks: https://trace.cafe/t/zV2CHLm4YP

I want to be able to reproduce it so we in the future could have performance regressions tests to find regressions.

Event Timeline

Peter removed a subscriber: Aklapper.

I guess this is because of the extra delay added on single clicks if the viewport is set to a specific size and using Chromedriver the browser "knows" that its a single click.