1. Prepare core and Larry skin for improved accessibility
2. Implement full keyboard navigation in main mail view
Fix list focus in non-keyboard mode: restore old behavior
Enable keyboard navigation on treelist widgets with cursor keys
Improve mail view document structure with headings, roles, labels and aria-attributes
Forward keyboard event through 'menu-open' command to enable keyboard navigation
Declare content language for proper text-to-speech support
Further accessibility improvements regarding keyboard navigation and document structure
Improve keyboard navigation on compose screen: define tabindex groups + enable keyboard controls of contacts list widget
Moved popup-menu functions to Roundcube core for seamless integration of (stackable) skin and core menus
Avoid scrolling when list gets back focus (on invisible focus element)
Set aria-selected and aria-expanded state attributes
Fix treelist keyboard navigation + assign aria-level attributes to treeitems
Use localized labels for voice-only headings and link texts
Set aria-* attributes for autocompletion fields and widgets
Replace Array.prototype.last() with jQuery.last to avoid side-effects in array iterations
Remove list row 'unfocused' state and keep 'selected' classes even when list loses focus. For visual distinguishing .focus tr.selected can be used
More aria-* improvements to toggle buttons and autocompletion lists
Improve (message) list widget display and keyboard navigation to show sane behavior with screen readers
Add message status labels to client
Localize title and summary attributes; make message count display box a live area