The render pass list data are recorded using run_benchmark with top real world sites. The CL that hacks into display.cc to do the recording needs to be applied to chromium: https://chromium-review.googlesource.com/c/chromium/src/+/1962628 The command line to use on Windows to record top_real_world_desktop: vpython3 tools\perf\run_benchmark --browser=release rendering.desktop --story-tag-filter=top_real_world_desktop For each site, all frames are zipped into a single file, together with one frame that with (nearly) full damage and maximum data size.