I'd start out using a Found Image condition to click the arrow – then type-select to get to the correct sub-menu – then a keypress to finish up.
If you're using Safari or Google Chrome or one of their variants that is scriptable then it may be possible to use a Execute a JavaScript in Front Browser action to perform the desired action, but that gets a trifle complicated.
I had been trying to use Find Image with a screenprint copy of the text I wanted clicked on - text does not seem to work with Find Image however. . I changed to only the icon and that worked fine.