1. copy some ancient greek text (unicode, utf-8), anywhere

2. press control-v, as if you "paste" it here

3. click on any word on the left panel

try copy/paste this text as example:

εἶπεν δὲ τοῦτο οὐχ ὅτι περὶ τῶν πτωχῶν ἔμελεν αὐτῷ ἀλλ᾿ ὅτι κλέπτης ἦν καὶ τὸ γλωσ­σόκομον ἔχων τὰ βαλλόμενα ἐβάσταζεν