Dear user,
I just released this console [https://mzl.la/30l3J06] for mobile browser and also for desktop. It contains a useful resource panel. It shows Local Storage, Session Storage, cookies, scripts, stylesheets, iframes, and image assets.
Best

update 18.07.2020 - Thanks for your feedback ... I understand your needs. At the moment I can help you by suggesting to you to add this js snippet [https://gist.github.com/chrahunt/e9b11ded0b3e691af9da] in your extensions to test the storage.local APIs..
Update me and inform me if it works