AltGraph is supposed to be true if Alt and Ctrl are pressed It's unclear if we want this. But I suspect some German sites might like us to support the AltGraph key, even in this synthesized manner. :) http://samples.msdn.microsoft.com/ietestcenter/domevents/KeyboardEvent.modifiers.html http://www.w3.org/TR/DOM-Level-3-Events/#key-AltGraph
Created attachment 123899 [details] speculative fix
Is this always the case in IE, or only for keyboard layout that actually have AltGr?
This bug is about keyboards which don't have an AltGraph key, or specifically operating systems which chose to synthesize AltGraph by the pressing of Alt + Cntl together. The question is if the Web should generally support such a behavior for synthesizing AltGraph, regardless of what the underlying operating system does. Bug 38241 and bug 40999 are more about the cases of supporting AltGraph where it's a real key and not synthesized in this manner.
What I'm saying is that even the synthesized behavior can be layout dependent. AltGr isn't useful on its own, it is just a modifier that lets you type certain characters easier, and that depends on layout. Anyway, I'd guess that any site that cares about AltGr also expects Windows and language-specific layout, and won't work well in a different environment.