Interesting how on a sub called "programming" there are literally no comments about the technical details (which are available in a public document) and instead everyone is threatening to move to Firefox, because a company that invests hundreds of millions of ad dollars into a completely free product appears to attempt to defend its source of revenue. This sub is a dumpster fire.

Based on the aforementioned public document, webRequest requires two process hops per request and does not support more than one extension at a time. Benchmarks by extension authors are not going to show a performance hit, because they are measuring only JavaScript execution time and ignoring the process hop overhead.

The proposed replacement API called declarativeNetRequest is similar to Safari. It's less powerful than the old API, but it has some interesting properties, for example it's possible to write an ad blocker that does not have access to your browsing history.