This was first reported on discord for Circuitissimo: https://mods.factorio.com/mod/circuitchips
The mod adds additional recipe/items to the circuit network technology, and when the mod was added to a save that already had the circuit network researched, the mods items weren't automatically unlocked.
Isn't factorio supposed to recalculate the technology trees to address this kind of scenario?
[0.17.79] Adding mods to an existing save - research issue
Re: [0.17.79] Adding mods to an existing save - research issue
No, you can loop through forces and do `force.reset_technology_effects()`