Good APP.
I give it 4 stars for this reason.
The developer of this APP needs to include a menu option for single item clearances, where the user can select what to clear instead of everything all at once. I refer to the menu selections of "Cookies Only" and "History Only", "Form Data Only", "Downloads Only", etc.

Keep the 1 Click All-Clear function, including it in the Options menu.

...and include the 1 Click clear menu option in the browsers context-menu (right click menu). The icon in the top bar can be used to list the above menu options.

Then this APP would be a full 5 Stars.

excellent for use

I'll give it 5 stars after I use it for a few weeks. So far I like it!

I've had a terrible time with hard drive fragmentation, and Firefox eliminated the size of its cache-size adjustment. Out of the box, the cache is 1 gigabyte!! (Allegedly, you can go into about:config and reduce that to 250 MB.) After a couple of hours of browsing, I've been getting 4000 fragmented files and 20,000 fragments. C'mon Firefox; have a heart.

But after clicking Clear Cache, the number of fragmented files drops to 200!

This Clear Cache add-on gives you a choice between clicking and getting a "notification" pop-up to confirm that the cache was cleared, or clicking and getting no notification. I think you need a notification to confirm the action occurred. But there should be an option to have the pop-up disappear after a few seconds, instead of requiring the user to click a tiny x in the corner of the notification each time. That would cut the number of clicks necessary by 50%.

muy practico y se invierte muy poco tiempo

Please create an option to disable F9 since this is also the shortcut do activate the Firefox read-mode.

Working with firefox 57 but not in 52.50ESR