When you encounter a problem with the appearance of your assistant's widget, check if you are receiving any errors through right click, inspect and go to the console tab.
If the error is giving "Range out of order in character class at new RegExp" like the one below, it causes that charset as missing or corrupted. As a solution, you can add the following command to the head tag of your script:
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />