Go to Chrome's Extension Menu by clicking on Window > Extensions or by going to the three dot menu in Chrome's upper right corner > more tools > extensions and click Details on the Resource Button
Find the link under "Inspect Views" that says background page and click it
click on the "Application" tab at the top, then "Clear storage" at the left
In the pane in the middle, click "Clear site data"
Refresh any sourcing tab and you should be all set