// by passing an object you can define default values e.g.: []
chrome.storage.local.get({userKeyIds: []}, function (result) {
// the input argument is ALWAYS an object containing the queried keys
// so we select the key we need
var userKeyIds = result.userKeyIds;
userKeyIds.push({keyPairId: keyPairId, HasBeenUploadedYet: false});
// set the new array value to the same key
chrome.storage.local.set({userKeyIds: userKeyIds}, function () {
// you can use strings instead of objects
// if you don't want to define default values
chrome.storage.local.get('userKeyIds', function (result) {
console.log(result.userKeyIds)
});
});
});