244730 - Position of abs element not recalculated on scripted layout change

Status: RESOLVED FIXED

(Core :: Layout: Positioned, defect)

Description

[Sebastian Redl]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8a1) Gecko/20040520
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8a1) Gecko/20040520

The page looks ok initially. After about 2 seconds, JavaScript will set the
display of one paragraph to none. This causes the body to shrink. Since its
position is relative, the absolutely positioned div "abspos" should be
repositioned too, but isn't and remains in the now incorrect position.
The bug doesn't occur if the div that wraps the paragraph "thep" is removed.

Reproducible: Always
Steps to Reproduce:
1. Load page
2. Wait

Actual Results:  
The text "Mispositioned text" stays where it was.

Expected Results:  
The text should have been repositioned to honour the "bottom" CSS rule.

Comment 1

[Sebastian Redl]

Attachment: Testcase

This is the same file as in the reference URL, just in case that one gets lost.

Comment 2

[Martijn Wargers (dead)]

This does not depend on scripting. It can also happen with css (:hover etc).
Resizing the window, makes the bug go away.
I think this bug is very similar to bug 225429, only there they use
position:absolute for the placeholder and here position:relative.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Not quite like bug 175364, but pretty similar issue....

Comment 4

[Sebastian Redl]

Flipping through several tabs also forces Mozilla to reposition, apparently it
doesn't cache all the tabs and reflows.

Comment 5

[Boris Zbarsky [:bzbarsky]]

Fixed by checkin for bug 261064