1342346 - [standards mode only] pressing button randomly toggles canvas scrollbars due to half-width overflow of border-collapse table borders

Status: UNCONFIRMED

(Core :: Layout: Tables, defect)

Description

[info]

Attachment: bug_firefox.html

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0
Build ID: 20170125094131

Steps to reproduce:

I wrote a simple html page, i divided the page in 4 divs instead of use a table. each div has a button with no action.

I have notice that this strange behavior is present only if i use html5 doctype instead html4.


Actual results:

If i click on the button in the right-top corner div (button BB) the page will be resize randomly.


Expected results:

The page should keep the same size.

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Something strange is probably happening with the scrollable overflow area calculations, which is making the scrollbars appear and disappear (as we search for a layout that is either stable with scrollbars or stable without them).

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

And it seems like it might be related to the half-width-overflow of the border-collapsed borders.