This mod reduces the number of displayed technologies to only those that have some available prerequisites and you can produce the required science packs. I've found this primarily useful when starting a new mod pack, to prevent information overload.

Only tested in SP. Any issues, please find me on discord discord.gg/WQYks7W, same handle as here.

Image details:
1.) Start of new game without Fogged Research
2.) Sans FR, with Adv. Electronics researched
3.) New game with Fogged Research
4.) Adv Electronics research with FR

Code adapted from https://forums.factorio.com/viewtopic.php?f=5&t=15563

Future plans
Research filtering (by mod)
Better science pack available handling

It seems that removing fogged research automatically re-enables all techs (new 0.17 handling?). So the following should no longer be necessary, and it should be safe to disable fogged research mid-game
Note: before removing Fogged Research from your game type the following command in the console to enable all techs, otherwise there's nothing to re-enable them. /c remote.call("fogged_research", "disable")

Applying to a current game, or updating fogged research version, will still show all techs until one is researched. - no longer applies