Firefox add-on similar to reader view

I am looking for someone to develop a firefox extension for me that scrapes a page of Japanese text and displays it one sentence at a time similar to reader view. Required features: - Scrape a html page and display text similar to reader view, but only one sentence at a time (see picture) - Addon must work for Japanese text - Change font size, family, color - Modify margins above and besides text - Change page background color - Configuration retained on reload - Load next sentence with left click on bottom right 2/3 of page, right arrow key, or space bar - Load previous sentence with left click on bottom left 1/3 of page or left arrow key - Save position in text until page is opened next time - Addon must work with yomichan popup dictionary addon