[Webkit-unassigned] [Bug 95911] New: Image drag and release results in a graphical glitch

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=95911

           Summary: Image drag and release results in a graphical glitch
           Product: WebKit
           Version: 528+ (Nightly build)
          Platform: Macintosh Intel
        OS/Version: Mac OS X 10.8
            Status: UNCONFIRMED
          Severity: Minor
          Priority: P2
         Component: Images
        AssignedTo: webkit-unassigned at lists.webkit.org
        ReportedBy: igeek1 at gmail.com


Created an attachment (id=162369)
 --> (https://bugs.webkit.org/attachment.cgi?id=162369&action=review)
video recording of bug

Summary:
If you start dragging an image (<img> tag) from a page, for example to save it to your desktop, and then release the drag while moving the mouse, the image glitches weirdly.

Steps to reproduce:
1. Go to a page, for example http://www.webkit.org
2. Start dragging an image on the page. I used the "Download Nightly builds" button image. A partially-transparent copy of the image will move with the mouse cursor.
3. While still moving the cursor, release the mouse button.

Expected results:
The partially-transparent image will animate smoothly back to the point where the drag started.

Actual Results:
The animation starts correctly, but about halfway through the animating image vanishes and reappears under the cursor at the position where it was released, and then fades out without moving further.

Regression:
I first noticed this when I installed the first public release of Mountain Lion (10.8). I have observed it in the latest stable Chrome (21.0.1180.89), latest Safari (Version 6.0.1 (8536.26.9)), and Webkit Nightly (8536.26.9, 537+).

Notes:
If you stop moving your cursor before releasing the mouse button, the animation works smoothly. It has the weird behavior only if the cursor is still moving when the button is released.

I have attached a video recording of this bug in action. The framerate isn't great but it gets the point across. You can see the bug best just after the 28 second mark if you step through one frame at a time. The video was recorded on the 10.8.2 developer preview with Webkit Nightly, but I've seen it in the aforementioned browsers.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.