Enanched reading for all webpages
Thanks to https://greasyfork.org/en/users/916309-rhdu, this is based in one of his scripts https://greasyfork.org/en/scripts/445268-bionic-reading

this script will add 2 buttons on right side medium height of the screen, for toggle bold and opacity
on load will apply the 2 of them by default

if you want to know more about the bionic reading look at https://bionic-reading.com/