403663 - Vertical position in web page while holding left mouse button on scroll bar and moving mouse in x-direction.

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Erwan Plougonven]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.8.1.9) Gecko/20071025 Firefox/2.0.0.9
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.8.1.9) Gecko/20071025 Firefox/2.0.0.9

When I left click on the vertical scroll bar and, with the left mouse button pressed, I move the mouse cursor in the x-direction until it no longer influences the scrolling, the page viewed jumps up several pixels.

Reproducible: Always

Steps to Reproduce:
1. In the middle of a web page, click on the vertical scroll-bar
2. Move to the left or right of the screen until the mouse cursor no longer moves the scroll bar

Actual Results:  
The displayed portion of the web page has moved up several pixels

Expected Results:  
The vertical position in the web page should have stayed the same

Comment 1

[Tyler Downer [He/Him]]

This bug was reported on Firefox 2.x or older, which is no longer supported and will not be receiving any more updates. I strongly suggest that you update to Firefox 3.6.3 or later, update your plugins (flash, adobe, etc.), and retest in a new profile. If you still see the issue with the updated Firefox, please post here. Otherwise, please close as RESOLVED > WORKSFORME
http://www.mozilla.com
http://support.mozilla.com/kb/Managing+profiles
http://support.mozilla.com/kb/Safe+mode

Comment 2

[Tyler Downer [He/Him]]

No reply, INCOMPLETE. Please retest with Firefox 3.6.x or later and a new profile (http://support.mozilla.com/kb/Managing+profiles). If you continue to see this issue with the newest firefox and a new profile, then please comment on this bug.

Comment 3

[dv5678]

This problem is so easy to reproduce, it should not have been dismissed over a mere lack of reply.
I retested it just now. (I didn't really need to, because I unintentionally reproduce this problem and curse it almost every day, since 1992.) This malfunction is Confirmed.
The affected Version is EVERY version of Firefox (0 through 41.0a2 so far).
The affected Platform is EVERY version of Windows (3.0 through 8.1). [I have not tested on Linux and Mac.]
This problem affects every Windows application that vertically scrolls a formatted page, plain text, or an image by means of a vertical slider. Testing just now on Windows 7, it happens in Explorer, WordPad, [MS]Paint, Command Prompt, Notepad2, and Firefox.
The original description is a little weak, so I'm re-stating it here. To reproduce: 0) View a page in Firefox (or ANY Windows application) that is long enough (tall enough) to need vertical scrolling. 1) Click down on a vertical slider and continue to hold it down. 2) Move the cursor some distance up or down, "dragging" the slider along. The slider will track the cursor (unless it reaches end-of-travel), and the page will shift some distance in the opposite vertical direction. 3) (Continue holding down the mouse button.) Now slowly move the cursor left or right, while minimizing any vertical motion. When the cursor exceeds 1 inch from the slider, the slider will snap back to the place that your dragged it from, and additional vertical movement will not affect the slider. If you move the cursor closer to the slider, the slider will leave its original position and you will regain vertical control of the slider. You can snap out and back in, any number of times, on either side of the slider. (If the window is close to the edge of the screen, you can only get far enough away from the slider on one side of the slider.)
Depending on what one is doing, this snapping out and back into control can be very annoying and frustrating. There is a weak argument for this behavior: If the user tries to drag the slider so far from its track, they might not know what they are doing. I think a stronger argument is: The horizontal position of the cursor should be irrelevant when dragging a vertical slider. That 1 inch or 100 pixels is an arbitrary threshold, and only serves to punish the user. It is a BAD behavior, and it has been around for far too long.
Because it affects so many applications so similarly, I suspect that this must be a Windows problem. If one writes a Windows program that presents a scrollbar, Windows imposes the 100-pixel rule and reports crazy slider motion back to the program. Unknown is whether this problem can be overcome, and how to do it. It might be a Windows setting (per-user or per-system), a Registry "tweak". Or it might only be correctable per-application, by use of parameters or an alternate way of creating a slider. If Firefox implements proper sliding, many many people would quietly appreciate this correction of an ancient, annoying, intentional MALfunction of Windows.
I think I have seen some instances where a dragged vertical slider fully ignores horizontal movement (like it should), but I can't pin down where. It must have happened in rarely-seen GUIs, like bootable hard-drive utilities or OS installers that boot from CD or DVD or USB using a non-Windows GUI toolkit, running on DOS or bare metal.