Canvas supports UTF-8
Canvas supports UTF-8 entry into the Rich Content Editor (RCE) and blanks in Quizzes. But how can you type characters that are not obviously on your keyboard?
For a Quiz, one method to enable users to enter a variety of characters that may or may not be on their current keyboard is to include the characters in the question - then the user simply uses cut and paste as shown below to enter the double left chevon. Certainly not as convenient as simply typing on the correct keyboard, but perhaps better than nothing.