Browser Vendor Status
While nightly builds of browsers can give you a chance to work with the latest features during their development and while they are still in an experimental state, browser vendors also provide useful resources for keeping up with the latest features and future roadmap of their browsers.
For the Chrome browser, you can keep up to date with current and future developments on the Chrome status website (https://packt.live/2qvpagS) and see what new features are being launched and how they are useful to web developers, The Chrome dev team's updates blog (https://packt.live/2PVR1Br) is also a great resource.
In the case of Google Chrome, information specifically about web dev tools improvements can also be accessed via the dev tools' "What's New" panel.