What is the controversy around gamete inter-fallopian transfer within Catholic moral theology?

I was listening to Pints With Aquinas July 29th episode with Trent Horn , he mentioned that a practice of gamete inter-fallopian transfer is an open question in the Catholic Church. What are the arguments for and against GIFT and what does that have to do with the use of a porous condom within marriage? (where does one even get a porous condom?)