Polylight

Polylight

Hello and welcome to Polylight, Polylight is a multi browser extension that lets you have a rainbow text highlighting color effect, don't specially want a rainbow highlight ? Worry not, you have the choice between solid colors and the RGB mode, in the solid color mode you have 6 presets with a section made to let you customize the color as you want it to be.

This is the remnant put back together with a nice UI and refactoring of an old extension I had made once to customize my highlight color and to add a rainbow effect, I hope you enjoy using it just as much as I do.

Performance Warning

Because of how browsers handle text selection natively, there is no generic CSS way to animate highlighting without forcefully injecting and updating CSS pseudo-elements (::selection). To make the rainbow effect work, the extension rapidly rewrites a <style> block directly into the webpage's HTML multiple times a second.

This is incredibly heavy for browser layout engines to handle and carries an inherent continuous CPU footprint while rainbow mode is enabled. I can't really do much about this natively without breaking the layout of the websites themselves, so it remains a known limitation of the RGB effect, but I did take all precautions to limit the impacts. (Also good to note that your result may change from mine as I'm using Firefox without hardware acceleration from what I know (meaning it doesn't use the GPU to be quicker), but maybe I'm wrong, and it'll always hammer the CPU, like any browser activity)

Features

Smooth Rainbow Mode: Custom time based loop to keep color shifts stable across webpages.
Solid Color Mode: Switch to a solid color and build your own custom preset library. The CPU impact drops to zero while in this mode because it only refreshes it once.
Smart Contrast: Text dynamically snaps to white or black only if the highlight combination becomes unreadable based on WCAG AAA standards.
Granular UI: Matte charcoal interface with granular sliders for speed, opacity, saturation, lightness, and because I prefer minimalism.