I want insight into the impact of browser extensions on users performance

Browser extensions have a negative performance impact on web sites and real users’ experiences. How big is this impact? It’s hard to measure because extensions are invisible to developers; they exist beyond our control and beyond our visibility. Gathering extensions, analyzing different metrics and diagnostics can help us better understand how different user experiences are between our development environment and the real world.

Of course, extension developers should also be auditing their own creations; but knowing the impact poorly-coded extensions can have on our sites can also help us build more resilient and better performing products.

One project has taken a stab at doing these sorts of audits: Exthouse. I’d love to see audits like this built into DevTools.