Hello! Huge fan of your products, they work great and make my life easier.
I have noticed with Chrome 64+ that there's been a few issues with the way Chrome extensions read the stylesheets, this has affected Re:view and LiveStyle it seems, as evident by the latest reviews on the Chrome Webstore.
In content-script.js in the Chrome Extension I believe you need to change this:
// find @import rules
if (item.cssRules) {
to
// find @import rules
if (item.hasOwnProperty('cssRules')) {