Whether it be bug fixes or enhancements you’ll likely need to update your extension after the initial release. The deployment process itself is exactly the same. You’ll have an additional option to deploy to a percentage of users for smoke testing. As stated before you’ll just need to update the version property in the manifest to a newer one. If you’re using source control make sure to tag your releases so if anything goes wrong with an update you can quickly revert back to a previous version. There will be plenty of enhancement requests that come your way once your user base grows but take all feedback with a grain of salt. If the feature enhancement doesn’t make sense for your product - don’t consider it. Users will ask for anything and everything but you’ll have the end decision on whether to push it or not. Tab Resize has had many feature requests - some that made sense and some that didn’t. The requests that did make sense have greatly improved the extension overall and it wouldn’t have been possible if not for users reaching out. When used correctly, user feedback can take your app to the next level.
Be sure to inform users of any updates or bug fixes that you deploy. An awesome new feature that isn’t discoverable is completely useless. I’d suggest adding a popup after the user opens up the updated extension so they’ll know exactly what has changed. You can use localstorage to store the current version decide accordingly what to do. Through the Chrome API you can also listen to install or update event and execute callbacks as required.