The inline JS link breaks the script-src Content Security Policy directive (this has been fixed in #17)
The data attributes to store the original font of page elements don't seem to exist, so when the resetFont() method is called, it is setting font-family to undefined on all those elements instead of restoring the original fonts
The reset link is broken in two ways:
script-srcContent Security Policy directive (this has been fixed in #17)resetFont()method is called, it is settingfont-familytoundefinedon all those elements instead of restoring the original fonts