Get all keys from Chrome Storage
Solution 1:
From the documentation (emphasis mine):
An empty list or object will return an empty result object. Pass in
nullto get the entire contents of storage. Don't forget to change "storage.sync" to storage.local if you're using local storage.
For some example code:
chrome.storage.sync.get(null, function(items) {
var allKeys = Object.keys(items);
console.log(allKeys);
});