This addon is so good it does what it's supposed to: clear cookies except whitelist, it does it well and doesn't have anything extra hogging around.

History and cache cleaners are different.

We need this addon for Chromium based browsers too: Kiwi, Lemur, Edge, Yandex... I reckon soon Opera, Vivaldi, Brave etc.

It seems it doesn't work as it intended to be.

Scenario 1
Go to your AMO, then close the tab, visit this link (farside), open the add-on, and you'll see there's a Mozilla cookie/localStorage in the list.

Scenario 2
Follow the scenario 1, close the browser, visit farside, open the add-on and you'll see the same thing.

I noticed it will only be triggered when I force stop the browser, reopen it and visit whatever website.

Well, I'm not sure when will it run either when a tab or browser closes, but I'd like to have both options in the settings. But don't delete just yet when multiple tabs still using the same domain.

Regardless, it would be better to have separate tabs for each category as cookies, localStorage, indexedDB and all.

Also please add these 2 words: localStorage and indexedDB in your add-on's description to make it clear. So the description may sound like this:

Deletes all cookies, localStorage and indexedDB from domains, not added to the provided whitelist, as soon as you exit your browser.

Last but not least, I'm using Iceraven browser if that makes it different.