Comment 79 for bug 1228250

> How many people still want this feature? In these days, most pointing devices support horizontal scroll with tilt wheel or swipe gesture.

Well, since you asked, here's the history of my horizontal scrolling capability.

First, my desktop still has a 1-dimensional wheel. After all, mice aren't the kind of gadget that have compelling reasons for people to upgrade them every six months.

On the other hand, my laptop is my primary computer, and I've recently upgraded to one with two-finger scrolling (in 2D). In fact, I've even written a Firefox extension (Scrolling Gestures) to take advantage of the horizontal scrolling capability. As a result, I've been untrained from using shift+scrolling and this feature isn't as important to me as it was a year ago (when each of my computers had only 1D scrolling).

> scrollable element implemented with JS is scroll normally with this patch

Do you mean, it will appear to JavaScript like Shift+Up and down? Bear in mind that there are two separate events for capturing wheel events; one ignores the axis and the other does not. There is at least one webapp (pressdisplay.com) that requires shift+vertical scrolling because of this. Here's a JSfiddle that demonstrates this: http://jsfiddle.net/SXAUx/7/ . Also, for the axis-capable event, shift-scrolling in Chrome reports only horizontal wheel events (even for shift+horizontal).

> And I'd like to know if other browsers have this feature?

Chrome has this feature. It also works in some other software, at least on Linux, like Evince (the GNOME PDF viewer).

I still think this feature is useful, even if I don't need it myself. However, I don't maintain Mozilla's scrolling code, so (speaking only for myself) if it's really too problematic to implement, I'm willing to concede.