explanation is here:
The “homophone explorer” script performs some data queries internally, rather than relying on an abstraction library such as the open-Framework.
In this particular case, the URL of the API token has changed recently (around March’19). So the URL needs to be updated in the body of the “homophone explorer” script.
Long story short - edit the “homophone explorer” sources, and replace the old SETTINGS_URL value with :
var SETTINGS_URL = ‘https://www.wanikani.com/settings/personal_access_tokens’;