I used Smooth Gestures without an issue. Installed yesterday Xubuntu 11.10, installed latest Chromium (18.0.1025.151, Developer Build 130497), Smooth Gestures was gone and nowhere to be found on the Chrome Market. Every other gesture plug-in I tried doesn't work and the issue seems to be the context menu - it comes up immediately upon clicking the right mouse button (on mousedown, rather than mouseup). I can see the mouse trails underneath but nothing happens.
Removed Chromium, got the stable Google Chrome from the website (again version 18 ) - same issue. Loaded up Ubuntu 11.04 with the same Chromium version (I think it had an update yesterday) - and the same thing - Smooth Gestures is gone, and I cannot find it anywhere. All other plugins do not work, and again due to the context menu.
There seems to be no option neither in Chrome nor in Gnome to somehow make the context menu pop-up on mouseup. The "Suppress context menu, when gesture failed" in "Gestures for Chrome" seems to do nothing.
Tried also deleting the user and starting with a clean profile - same thing.