It would be really useful, and something that I haven't seen in other profiling tools, if we could take a profile of a given build and then compare it to a profile from another build. This would be especially useful, for example, for debugging increases in the time required for talos tests. (Or really, debugging _any_ increase in processing). I'm sure this is a pretty daunting task, and can probably be broken into several smaller tasks.

We've been discussing this feature recently. I'm working on getting mechanism for automated profile collection. Once these are done I'll take a look at this.

Moved to https://github.com/devtools-html/perf.html/issues/470 .