Context menu on button

I created a three buttons button.
A left click opens a folder in the same tab and the right click opens that folder in a new tab.
But I would like to display the context menu of that folder when I right click the button (like what happens when you right click on a drive letter from a 'Go DRIVEBUTTONS' button), and have a middle click open the folder in a new tab.
Is it possible to display the context menu of a certain folder on a button (I know the middle click part is possible)?

Go PATH="C:\xyz" CONTEXT on a normal button (not a three button) will turn into something which shows the context menu when you right-click it, and goes to the folder when you left-click it.

(The Go command's CONTEXT argument is currently hidden/undocumented, but is what Go DRIVEBUTTONS generates internally. It's possible this may stop working in the future, or we may document it and make it officially supported.)

Thanks, that works.
Followup question though, if this can't be used in a three buttons button is there an other way to have the folder open in a new tab with a middle mouse click?
I've tried multifunc and multifunctab but that removes the right click context menu.

AFAIK there isn't a way to combine both at the moment, except maybe by having a script on the right-click action which causes the context menu to appear. (Not sure how easy that is to do from a script, though. Scripts can show their own menus but I don't know if there is a way to make them show the context menu for a file without generating the contents of the menu.)