1025524 - Deprecate Fullscreen permission modal dialog on OSX

Status: RESOLVED INVALID

(Firefox :: Untriaged, defect)

Description

[Florens Verschelde :fvsch]

The fullscreen modial dialog is a pain in daily use, getting in the way of users who *most of the time* willingly clicked a “Yay let’s show this fullscreen!” button on a website; it is also rendered obsolete as a security feature (for those times when it would be used by attackers) thanks to the current behaviour of element.requestFullScreen() on OSX.

Being a unnecessary pain inflicted to users, I suggest that it should be removed altogether on OSX, and any platform where it is similarly useless.

This is the reason why it’s unnecessary as a security feature on OSX 10.9 (and I suspect 10.7+): 

When using element.requestFullScreen() Firefox 32 on OSX 10.9 now:
A. Animates the window to OSX fullscreen mode (visible animation that takes almost a full second).
B. Keeps the tab strip and navbar visible.
C. Shows the fullscreen permission dialog (as a modal overlay).
D. Exits fullscreen mode when the user clicks on a tab for a different page.

The original intent of the permission dialog was to prevent phishing, in which attackers would mimick the browser’s UI (and possibly the OS UI) in HTML in the page itself, pretending to be a different site by showing a fake URL and so on.

The behaviors mentioned in A and B — especially the latter — make those theoretical attacks inefficient. Hence the behaviors in C and D are unnecessary and probably not much else than a nuisance.

Additionnally, D should be removed as it’s inconsistent with the behavior of the tab strip in Command-Shift-F fullscreen mode, and that difference in behavior is not predictable or reflected in the UI.

Comment 1

[Florens Verschelde :fvsch]

I did other tests and apparently I was wrong about the current behavior. By default Fx 32 doesn’t keep the tab strip and navigation bar visible with element.requestFullScreen(). I must be getting this result because of some preferences set by an extension I tested then uninstalled on that profile. A clean profile doesn’t have this issue.

Comment 2

[Florens Verschelde :fvsch]

To be exact:

- When browser.fullscreen.autohide=true (default), Fx will hide the tabs and navbar on element.requestFullScreen() (not with the main window full screen mode).
- When browser.fullscreen.autohide=false, Fx will keep the tabs and navbar even with element.requestFullScreen().