Watching posts for changes is an extremely heavily requested feature on Stack Exchange (see 1, 2, 3).
This extension adds a 'watch' button to the actions under every post on the Stack Exchange network, letting you keep track of edits, vote changes, post state changes (e.g. closures), new comments, and new answers!
Now you can easily go back to a post once it's been modified to reconsider your vote or comments, or because you wanted to know the answer yourself!
It is available for Firefox and Chrome.
The extension adds an unobtrusive icon to your extension bar and adds a small coloured badge when a change has been detected. It checks the API every 10 minutes for any changes to posts in your watch list. It will prompt you for an access token on first install to give it a higher quota for querying the API.
If you would like any additional watch options, please make a feature request as an issue at the Github repo: https://github.com/shu8/stack-exchange-post-watcher/issues. I'll try my best to add it in!
Any feature requests or bug reports are very welcome! Please post them as an issue on Github.
If you would like to help by submitting a pull request for a bug fix or new feature, please feel free to do so! To add a new watch type, it might be as simple as adding just one line, so please have a go if you want!
Chrome:
Firefox: