I tried using grayscale filters on my devices previously and reverted within a day. I am trying this again, this time with more consistency. This is to avoid my dopamine levels spiking out of control.
On Android devices, this feature is built-in. If using LineageOS, go to Settings -> Display -> Live Display -> "Reading mode" to toggle the switch.
On desktop, I am using this for Firefox alone for now. Go to addons, search for "Grayscale" and pick one.