I would like the ability to create a highlighting layer for a particular purpose which I can turn on/off independently of other highlighting I might have in that resource. For example, someone was recently asking about how to find all the questions of Jesus. I couldn't think of a way to search for them, but I suggested finding them all manually (with the help of a couple of printed books that list them all) and marking them with a special highlighting style you create for the purpose. But then I'd want to be able to turn those on/off, just like I can turn on/off red letter text. However I wouldn't want it to turn off my other highlighting. I'd want to be able to name this "highlighting layer" (e.g., "Questions of Jesus"). I'd need to be able to set which highlighting layer I'm working in at any given time (the default would just be the normal one that we use now), such that whatever highlighting I add while that layer is active goes into that layer alone. And that layer would need to appear in my visual filters menu so I could turn it on/off independently. I could overlay as many highlighting layers on top of each other as I wanted. If there was a conflict (e.g., some text highlighted with two different styles in two different layers that are both active at once) then there'd have to be some heuristic to determine which one applies. The most recently turned on layer? Or the most recently created highlight?
