1016414 - 'Left' should alias 'up' and 'right' should alias 'down' (flipped for RTL) when keyboard navigating a <menugroup>

Status: NEW

(Firefox :: Menus, defect)

Description

[Jared Wein [:jaws] (please needinfo? me)]

<menugroup> already supports 'up' for going to the previous sibling element, and 'down' for going to the next sibling element. <menugroup> is by default a horizontally laid out item, so trying to navigate using the horiztonal arrow keys may be attempted by people using the element.

Comment 1

[Neil Deakin]

The code that handles keyboard menu navigation is in nsXULPopupManager::HandleKeyboardNavigation and nsXULPopupManager::HandleKeyboardNavigationInPopup.

One thing to be careful of here is that left/right normally open and close submenus, so you'll need to handle the case where someone puts a menu in a menugroup. This means that you probably want to implement this as if the menugroup was a menubar (see the end of nsXULPopupManager::HandleKeyboardNavigation).

Comment 2

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

I don't think that ArrowLeft/ArrowRight should be alias of ArrowUp/ArrowRight because when "Back" is active, users must expect that ArrowDown key causes moving below. I.e., "Save Page As..." should be active.

Comment 3

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

I mean, moving left or right by ArrowUp/ArrowDown is not natural behavior visually.