Adds a button to hide Bookmarked picture in 'ppixiv for Pixiv'
(https://greasyfork.org/en/scripts/370418-ppixiv-for-pixiv)

My code below is NOT optimized and only for my personnal enjoyment


I needed a button to hide the bookmarked picture for better concentration on the ones I haven't took a close look at
My button placement is fast to access (which I like), but may be awkward for a general purpose

The button must be clicked each time to hide newly bookmarked images or images that loaded after


20/09/2022 - updated with a menu and now with the Blacken option and the Show back option
05/02/2023 - code was broken due to new update, fixed it
16/02/2023 - close menu automaticaly + added logo for each option (gallery : https://imgur.com/a/ju03rOD)
04/04/2023 - when changing page the button would disappear