Rocketbar's collapsibility doesn't track the page's scrollability as the page is zoomed



Firefox OS
4 years ago
3 months ago


(Reporter: botond, Unassigned)


Firefox Tracking Flags

(Not tracked)




4 years ago
  1. Load a page that cannot initially scroll vertically, but which
     can be zoomed.
  2. Observe the rocketbar cannot be collapsed. So far, so good.
  3. Zoom the page in, so that it can now be scrolled vertically.

Expected results:
  The rocketbar can now be collapsed.

Actual results:
  The rocketbar still cannot be collapsed.

Conversely, if you start with a page that is scrollable vertically, and then zoom out so that it isn't, the rocketbar remains collapsible, giving the user the false impression that the page is still scrollable vertically and thus they haven't zoomed out as much as they should be able to.

I think the ability to collapse the rocketbar should change dynamically as the ability to scroll the page vertically changes with zooming.

Comment 1

4 years ago
I guess I can see how this might be a bit difficult: if the rocketbar detects that the page is at its minimum zoom given its current composition bounds (including the offscreen bit that scrolls on-screen when the rocketbar collapses), and becomes non-collapsible, that makes the page's composition bounds shorter, making the page zoomable again...

Comment 2

4 years ago
So I don't think we want pages that have become scrollable (where when I say 'scrollable', I mean that it has become possible to collapse the rocketbar) to become unscrollable again. There are too many issues with this, similar to what you say in comment #1 and I massively regret doing it that way in fennec :)

On the other hand, if you zoom in, the rocketbar should become collapsible. This sounds to me like a platform bug - zooming in has changed the scrollable area of the page, but we don't get the event from the browser iframe. I suppose that the values we get back from the iframe probably don't take into account zoom at all...

Do we want separate events for zoom changing, or do we want those values to take into account zoom? Would appreciate opinions on this, I think the latter but I don't feel strongly about it.
Which event are you currently listening for to determine scrollability?

Comment 4

3 months ago
Firefox OS is not being worked on
Last Resolved: 3 months ago
Resolution: --- → WONTFIX
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