Effects dependent on the technology being researched

[Ignatus]

I want a new "Player"-range requirement for effects like "ResearchingTech". This can be used for things like making each Sea tile produce a bulb while the player is researching Seafaring, or giving the Chinese double Science bonus for discovering Gunpowder. This looks more funny then giving whole techs.

[Lachu]

It's quite similar to eureka system in Civilization 6 and Progress. In progress you can increase bulbs to some technology, which don't have to being researched. Difference between your idea is that eureka is not depending on currently researching status.