Using Web Access with Firefox (on Linux at least) and pressing the Menu key results in Firefox also opening a context menu, rather than just sending the key through to the session. Chrome seems to work fine though.
Upstream has also noticed this and fixed it:
Tested this after the vendordrop for Firefox and Chrome on Linux and it works as intended for both browsers now. The key is sent to the session.
The release notes got merged with those for bug 6152. But they looked good before that. :)