If your machine is a bit on the old side or just low on RAM, being able to uninstall a browser extension is always cause for celebration. Of course, there are always users who like to free up all the resources possible, plentiful or not, not to mention those who want the latest bleeding-edge changes from upstream in their daily-use software. If you fall into any of the categories named above, Fran§ois Beaufort and his team of crack Chrome experts have some good news for you. As part and parcel of the new Media Router tech that's being built into Chromium, beta builds of Chrome with the latest upstream changes, as well as Chromium, have a hidden flag that allows you to ditch the Cast extension and free up valuable RAM while browsing.
Chromecast owners who want to get rid of the Cast extension once and for all and are either already running the latest and greatest or are willing to make the jump from a stable version will find a few new flags to play with. Among them, chrome://flags/#media-router will allow you to flip on and off the new "Media Router" feature set. Part of this feature set is the capability to cast a web page to your Chromecast or other compatible receiver by right clicking anywhere on the page, as simply as you might save an image. From there, just click "Cast" and you're in business.
As with any new, unstable code or new, unstable application versions, caution should be exercised and perfection should certainly not be expected. The feature is only hidden deep in the beta revisions of Chrome for certain platforms, for the time being. Android, even on the Chrome Dev app, is left in the cold. As with all new Chrome features, of course, should this be successful and receive a good response from beta testers, normal users will likely see the capability hitting their own browsers fairly soon. No specific time-frame was given, since the feature is still in development, but features that hit the beta builds for users to play with normally don't have much longer until they're ready for prime time.