I've been trying out Orion for a bit and so far find it very impressive. I've been using it in combination with the VoiceOver feature built-into Mac OS, and for the most part the interface works great. The one exception to this is the tabs area.
To reproduce, turn on VoiceOver with command-F5, then use CTRL+Option+Arrow keys to navigate through the interface, and CTRL+Option+Shift+Down and Up to go in and out of sections like tool bars or the web content.
Currently, the tab area shows up as an unlabeled scroll area to VoiceOver. If you go into it, each tab is broken up into 3 elements, a button which always seems to be dimmed, the title of the page, and 2 images one of which is sometimes labelled as "Globe". While you can press CTRL+Option+Space on a tab to switch to it, pressing CTRL+Option+Shift+M to bring up the context menu for the tab doesn't work.
How I'd expect this to read with VO is how other browsers handle it which you can try for comparison. The tab bar is read out as a group, and every tab shows up as a single "tab" element, with the active one being marked as "selected". Additionally you can press the CTRL+Opt+Shift+M to get the menu to appear.
