I have quite a strong colour vision deficiency. One way it affects me is that I often miss red text on a dark or green background.
I used to have an app on my phone that would shift colours from the camera, so that I could at least see where the colour changes, if not give it a name. At some point that app stopped working with new versions of Android
This morning, while the kids were playing Minecraft, I spent a few minutes making a little web page that shows your webcam feed, and applies a hue-rotate filter to it. Nice and simple!
In case anyone's interested in my process, here's a recording of my "see colours any%" speedrun:
https://media.aperiodical.com/colour-shuffle
The page itself is at https://colour-shuffle.think.somethingorotherwhatever.com/index.html
(if you don't have a camera it'll just look like an empty page)