See the uploaded test.html, it provides a case to prove that the current svh(and its logical version) isn't 100% safe to avoid obscuring page contents.

When the search bar in the bottom is opened or hided, the size and the position of the content of test.html get obscured, which does not comply to what the W3C document suggests.

Edit: obscured => reflowed

You mean in Firefox desktop or mobile? In desktop the search bar changes the height of the viewport.

(In reply to Emilio Cobos Álvarez (:emilio) from comment #1)

You mean in Firefox desktop or mobile? In desktop the search bar changes the height of the viewport.

I mean the desktop version(I set the platform item to Desktop).
Yes, it changes the height of the viewport, so contents streamed in vertical direction could get obscured.

But content isn't obscured, it's reflowed because the viewport is smaller. What am I missing?

(In reply to Emilio Cobos Álvarez (:emilio) from comment #3)

But content isn't obscured, it's reflowed because the viewport is smaller. What am I missing?

Sorry for the wrong word, it is correct to call it "reflowed".
Whatever, the viewport is changed, so it's an unexpected UX if I am using a "safe" svh, isn't it?

Well, not really. That's been the behavior for ages, vh / vw change with that. So this is mostly a proposal to change the Find UI inside Firefox, more than a bug in the style system.

(In reply to Emilio Cobos Álvarez (:emilio) from comment #5)

Well, not really. That's been the behavior for ages, vh / vw change with that. So this is mostly a proposal to change the Find UI inside Firefox, more than a bug in the style system.

I think you meant Bug 869543 . I'd be glad to see this issue resolved either way, let's remain this issue as open, while tracking Bug 869543, if Bug 869543 is fixed, this bug can be closed.

The severity field is not set for this bug.
:enndeakin, could you have a look please?

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