Re: getThisTabMedia

Isn't it just the current tab - there is no selecting done by the user - a
better name would likely be getCurrentViewportMedia or something along
those lines

On Sun, 4 Oct 2020, 02:44 Silvia Pfeiffer, <silviapfeiffer1@gmail.com>
wrote:

> I love the idea.
>
> How do you suggest the application would be able to identify the "tab"
> without the user selecting it?
> Would it be based on a text filter, e.g. getTabDisplayMedia("Screen
> Capture") would then identify the "Screen Capture" tab because of its
> naming?
> Would it automatically pick the first such available or would it bring up
> a picker dialog again if there are several matching ones?
>
> Cheers,
> Silvia.
>
>
> On Sat, Oct 3, 2020 at 12:40 AM Elad Alon <eladalon@google.com> wrote:
>
>> Hello all,
>>
>> We're proposing an API that would be very similar to
>> navigator.mediaDevices.getDisplayMedia
>> <https://www.w3.org/TR/screen-capture/#dom-mediadevices-getdisplaymedia>,
>> but which only will be able to initiate capturing of the tab from which it
>> is called (rather than provide the much wider selection of share-sources
>> that getDisplayMedia has).
>>
>> In the case of getDisplayMedia, the Screen Capture TR
>> <https://www.w3.org/TR/screen-capture/> says (bold-emphasis mine):
>>
>>> The user agent MUST let the end-user choose which display surface to
>>> share *out of all available choices* every time, and MUST NOT use
>>> constraints to limit that choice.
>>
>>
>> This will be true for getThisTabMedia too, but there, the only “available
>> choice” is the surface from which it is called (specifically, the browser
>> tab). We’ll be sending a PR similar to this one
>> <https://github.com/eladalon1983/mediacapture-screen-share/pull/3>
>> against the Screen Capture TR fairly soon.
>>
>> The *main benefit* of this new API is that a simple accept/reject dialog
>> can be presented to the user, rather than a complex picker
>> (screen/window/tab).
>>
>> *Contrast getDisplayMedia picker in Chrome:*
>> [image: image.png]
>> *Potential dialog-box for getThisTabMedia:*
>> [image: image.png]
>>
>> We think that the security properties of own-tab capture are no worse
>> than the version that goes via the picker. We note that the application
>> will have control over the surface that is being displayed, and that can
>> cause some sharing of information that would otherwise be inaccessible,
>> such as colors on visited links, or content of embedded frames, but we
>> think that the risks are no bigger than for regular sharing, and that the
>> proposed, simple, prompt is good enough to mitigate this concern.
>>
>> Your feedback is hereby solicited. :-)
>>
>> Thanks,
>> Elad Alon
>>
>