Type poynesian characters (w/macrons) into web pagesThis extension will allow you to type Hawaiian (Polynesian) characters into any web input controls.
alt + <vowel> key combination to enter the vowel w/macron
Double tapping the shift THEN hitting a vowel will get you an uppercase vowel w/macron:
shift, shift THEN <vowel>
alt + ' will get you the glottal stop character or ‘okina
If this doesn't work for you then the input has been blocked by the creator and you should try using Polynesian Text extension: