You can also do this from mobile, too. Tusky has an "Open in browser" option. There are other clients and most likely they all have the same option.
NOTE: Remember if you're viewing a post from another instance, if you try interacting with it you'll get a dialog asking you to verify from where you are logged in on, because the other instance does not know about you.
Of course, you can always go back to your native view and interact with it as you normally would.
samhainnight