Over the past few days, it is no longer possible to clear the browser cache with a single click in the preferences. Instead you have to select "clear data" then uncheck "Cookies and Site Data" and validate. Clearing the cache is something you do rather often when developing and testing a site (or testing gecko). I do it several times per hour. Could we re-add the simple clear cache button in nightly or developer edition?

Johann, is this something that the storage project can look in to?

Looks like this was done deliberately in bug 1422163 - so wiring it up. I think this qualifies as a P5 for now from the Preferences perspective, but let's hear back from the Storage folks and revisit if needs be.

Yeah, I fully agree and I think the best solution would be to remember the state of that dialog like we do in clear history. To give a bit of context, the privacy UI revamp consists of multiple projects, one of which was the consolidation of all site data (cookies, quota storage, cache, etc.) in a single section in about:preferences. That resulted in the clear site data dialog which we're not too happy about since it duplicates some functionality with the adjacent clear history dialog. So we've been planning to merge (and improve) the clear history and clear site data dialogs, so that this issue would resolve itself. I understand that it would still be 2 clicks instead of one, but considering that you also need to open about:preferences anyway I would highly recommend to use an add-on like https://addons.mozilla.org/en-US/firefox/addon/clearcache/ instead.