624169 - invalid form popup can be partially offscreen; "ASSERTION: Popup is offscreen"

Status: NEW

(Core :: XUL, defect)

Description

[Mounir Lamouri (:mounir)]

From layout/xul/base/src/nsMenuPopupFrame.cpp:1279

The popup can be offscreen. That's an expected behavior. I don't even think we should WARN here...

Comment 1

[Neil Deakin]

No, popups should never be appearing offscreen. It is definitely an error if mInContentShell is true.

Comment 2

[Mounir Lamouri (:mounir)]

I have this assertion when I have a popup appearing at the left of my window and the window is at the left of the screen. A part of the popup is then offscreen. What should be the correct behavior?

Comment 3

[Neil Deakin]

What happens if you have the patch in bug 524545 applied?

Comment 4

[Mounir Lamouri (:mounir)]

(In reply to comment #3)
> What happens if you have the patch in bug 524545 applied?

Yes. If the window is close enough to the border of the screen.

Comment 5

[Neil Deakin]

Do you have a testcase?

Comment 6

[Mounir Lamouri (:mounir)]

You can open oldworld.fr/mozilla/input-style.html, put the window at the left of your screen, click on the first input element and press enter.

Comment 7

[Neil Deakin]

That arrow panel in that test appears onscreen for me.

Comment 8

[Mounir Lamouri (:mounir)]

Attachment: Screenshot

This screenshot shows the problem. When the page is partially hidden, if I tries to submit the form in an invalid state, I will see the popup partially hidden. I don't think it could be done otherwise. What should happen in that situation?

By the way, it's interesting to see that the offset is completely ignored in that situation even if the popup didn't move. Ironically, this make the popup even more hidden (given that the offset would have move the popup on the right).

Comment 9

[Jesse Ruderman]

Attachment: simple testcase (window must be at left screen edge)

Comment 10

[Mounir Lamouri (:mounir)]

But I don't think there would be a way to have it inscreen given that the element can be fully offscreen.

Comment 11

[Mounir Lamouri (:mounir)]

By the way, I get this assertion multiple times with the following test:
toolkit/content/tests/chrome/test_arrowpanel.xul