I'll give an example since I'm tooting so loudly about this, my job entails a lot of R&D and distributing knowledge to other engineers in a concise manner. I use an app called hypothesis- https://web.hypothes.is/ which is very popular in research groups.
What it does is it lets me essentially annotate websites. So for instance I have an application with a front end UI, instead of writing readmes with no interaction to the front end UI I can actually annotate each page like a how-to, or a help doc. You go to that specific URL and get notified that there's a hypothesis doc on it to read.
When I used to work at a k8s distro company I used it to help teach people how to deploy clusters, etc.
Another one is Dark Reader that makes every single website dark mode.. Ublock I can't even remember a time of my life not using to block ads.. I do have null stuff via cloudflare dns as well but still use ublock everywhere since it's also a massive security improvement blocking chaotic javascript.
It's amazing for training situations.