Once a remote tab is received, we should automatically add it to the tabs tray - but probably not switch to it right away. We should display a Snackbar prompting user to switch to the just-received tab. Essentially, receiving a remote tab should feel just like opening a link in a new tab.

Careful. There are two properties that are worth preserving: * Send Tab can open a non-Firefox app. If I send a Google Maps link to my phone, it's awesome when it opens Maps. * If I send a link to a music page, I don't want my phone to spontaneously start playing audio. More generally, just because I sent a tab doesn't mean we should load it right then, unless we can guarantee that it won't start burning CPU or network.

We might not want to load the website immediately, however while I'm in the browser I expect the tab "to arrive inside the browser". Having to check the notification tray is somehow inconvenient. Using a heads up notification (bug 1300222) might be better (but introduces sound/vibration). Flagging antlam for some UX input.

I agree with rnewman and sebastian here. Loading the website immediately is problematic. We should look to iterate towards a more "responsive" experience down the line. But in the meantime, it makes sense to prevent things like media autoplaying in the background as soon as a tab is received. Our media controls work also complicates this picture further. To scope down this bug, I think we should focus on the use-case where the user has Firefox open, and just received a tab. In that case, we should show a snack bar, giving the user a choice to switch. This, in addition to the current notification that they're getting in their notification tray. Once the user presses on either, it will load the tab. Nothing changes if the user does not have the Firefox open on their device.

Decided to go ahead with the "heads-up" notification instead of a snackbar, see Bug 1300222. This bug is a no-op then. It might be worth investigating adding tabs into the tabs tray - but that comes with a set of considerations, rnewman gave a few (Comment 1).