[nieve]

> HTML filtering is the ability to filter the response body of HTML documents before it is parsed by the browser.

> For example, this allows the removal of specific tags in HTML documents before they are parsed and executed by the browser, something not possible in a reliable manner in other browsers. This feature requires the webRequest.filterResponseData() API, currently only available in Firefox.

https://github.com/gorhill/uBlock/wiki/uBlock-Origin-works-b... I'm going to trust Gorhill on this one. If a significant feature _does not exist_ in Epic then the only way that it couldn't hurt performance is if it was somehow useless. I suspect the Epic people (accidentally?) didn't measure that aspect.