Issue Summary

Users are unable to authorize and use the GitHub Power-Up in some browsers (Google Chrome and Firefox).

Steps to Reproduce

Unable to reproduce the issue.

Expected Results

Users should be able to authorize Trello's access to their GitHub accounts as well as to be able to view branches, issues, pull requests, and commits attached to cards. 

Actual Results

Users can't authorize Trello's access to their GitHub accounts. They can't also view the branches, issues, pull requests, and commits attached to their cards. 

Workaround

Users can use the Safari browser (if they’re using a MacOS device) or a different browser (e.g., Microsoft Edge) since the problem only affects Google Chrome and Mozilla Firefox.

Alternatively, clearing the browser's localstorage may help.

To do so:

1. Open the browser console while viewing a Trello board with GitHub enabled and check the Application tab.
2. From there, you should see a Local storage section on the left, under Storage.
3. If you see an entry for https://github.trello.services/, try to clear it (right-click and then Clear), then refresh the page and try to authorize the Power-Up and use it. 

Update Nov. 21
The following workaround has also provided success and should be tried before clearing localstorage

1. Go to the Network tab in the developer tools on your browser
2. Click "disable cache"
3. Refresh the page