How can I add a Right Click modifier to a Button Menu?

Are there any mouse click modifiers available for handling the right and/or middle mouse clicks in a Toolbar Button Menu?

Additional Info:
I do see how to add the @keydown modifier for including a Ctrl, Shift or Alt mouse click., but not right or middle options.

I am also aware of the "Three-button", but those are not meeting my desire to Ctrl, Shift or Alt right click a Button Menu.

Note: This function works great for @keydown modifier:

@keydown:none
calc.exe
@keydown:shift 
notepad.exe

Three-Buttons let you run different commands for left/right/middle clicks.

Within some or all of those commands, you can then also use @keydown to modify what they do based on shift/ctrl/alt in addition to the mouse buttons.

I guess there are no Right Click, Middle Click modifiers available for a "Button Menu" that is not a Three-Button.

Perhaps, maybe, pretty please... modifiers can be added to a future Dopus release?

That’s what Three-Buttons are for.

You can use a User Command or Script Command if the issue is not wanting to repeat the common parts of each mouse button’s command.