In Firefox, you can use the cookie autodelete extension (it's open source) which deletes all cookies for sites you haven't explicitly whitelisted. Same thing, integrates well with other privacy features on Firefox (like container tabs and I still don't care about cookies, and is probably better maintained than the feature in DDG.
IMO starting with a more minimalistic base, and adding whatever features you need is a better approach that suits more use cases. Just reduce your extensions to what you really need, and deactivate or uninstall those you don't need. Make sure what you are installing is open source, well-maintained and trustworthy (look at the github page: when was the most recent commit or release? how many contributors and stars are there? It's not foolproof, but a good start and definitely beats closed source extensions). Having access to more extensions is not a bad thing.
EDIT: don't use I don't care about cookies as it was acquired by some shady companies. Use the independent fork called I still don't care about cookies instead.
And how does that work? How do you unmount the root directory of a live system and invoke a script?