How to copy text from one tab to another?

Question

I am working on an extension that allows me to copy data from a website on one tab to another open on a different tab. The two websites have different origins. I tried browser.storage.local but it doesn't seem to be working:

Storing data:

browser.storage.local.set({
  'title': 'some title',
  'date': 'some date'
});

Retreiving data:

let promise = browser.storage.local.get(['title', 'date']);
promise.then(function(item) {
  console.log ('promise success');
  console.log('title: ', item.title);
}, function(error) {
  console.log('error', error);
});

Why is it not working and how do I fix it. Thanks in advance.

Answer 1

I just figured it out, it requires a storage permission. I added the following line to my Manifest.json file and it worked:

"permissions": ["storage"],