Integration with the rest of Google's services. More specifically: when logged into my Google account Chrome will automatically sync my browser history and bookmarks between devices. Adding a device is as simple as logging into a Google Account. No extra plugins to download and install, it just works. And the browser experience is uniformly good across devices.

In Chrome developer tools I daily use the workspace tools to edit CSS and other files, and see the updates in real-time in-browser.

I honestly don't know if any of these features are available in Firefox. If they are I would try it out and consider switching.