Don't really understand much about all the serious vulnerabilities
now corrected in the latest 52.1, just released 4/19--there are a lot of them--but doesn't look like this particular unicode exploit is covered. Thanks for the heads up.
Firefox users can protect themselves by entering "about:config" in the address bar and agreeing to the displayed warning. From there, enter "punycode" in the search box to bring up a line that reads network.IDN_show_punycode. Next, double-click the word "false" to change it to "true." From then on, Firefox will display the "dumb ascii" characters and not the deceptive, encoded ones.