868010 - <select> options cannot be clicked (pointer offset?) with Retina display and a secondary monitor, and sidebar open

Status: RESOLVED DUPLICATE of bug 853252

(Firefox :: Untriaged, defect)

Description

[Steve King]

Attachment: test.zip

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:20.0) Gecko/20100101 Firefox/20.0
Build ID: 20130326150557

Steps to reproduce:

I've only been able to reproduce this in very specific circumstances. My system is this:

* Firefox 20.0 (haven't tested others)
* MacOS X 10.8.3 (haven't tested others)
* MacBook Pro with Retina display (haven't tested others)
* Non-Retina external monitor (FF window is on the built-in display, but this problem does not reproduce when the external monitor is absent)
* Sidebar open (does not reproduce without sidebar open)
* <select> element at least 500px to the right of the left page margin (does not reproduce with the element nearer to the margin; actual distance may be related to sidebar width)

Click on the select element. The drop-down list appears, but the elements cannot be selected by mouse click. They can be selected by pressing ENTER on the keyboard.


Actual results:

I think this is some sort of bad interaction between the hidpi and non-hidpi displays, affecting the pointer offset calculations when the sidebar is open.  I've attached a zip file with a minimal test.html file and a pair of screenshots.  The screenshots show the pointer in an odd location, *not* the location that it appears on the screen.  (This seems to be a problem with the OSX screenshot program unrelated to Firefox, as it happens with screen shots of other apps or even a blank desktop as well.)  I've annotated the screenshots to show the actual, visible pointer location.  In the first one, the drop-down is not expanded and a bit of JavaScript reports the appropriate pointer location.  In the second one, the drop-down is expanded and the JavaScript reports the wrong location.  It looks like the reported location is near where the screenshot shows the cursor (hmmm...) relative to the FF pane. Also, notice in the 2nd screenshot that the bookmark in the bookmark bar is highlighted as if the cursor was hovering over it.

This may be related to bug #829886, though that one is supposedly fixed in FF 20.0.


Expected results:

Should have selected the option normally.

Comment 1

[Timothy Nikkel (:tnikkel)]

I think Jonathan Kew recently fixed an issue like this, you might try a pre-release Firefox version to see if it is fixed.

Comment 2

[Jonathan Kew [:jfkthame]]

Probably bug 853252; should be fixed in a current build from http://nightly.mozilla.org. (Steve, please confirm whether this fixes it for you - thanks.)

Comment 3

[Steve King]

That certainly sounds like the same bug, and the problem is taken care of in the nightly. Marking as duplicate.