Do i2c blocks work?

I’m not sure how to use the i2c blocks in MakeCode Arcade. If I load the feather extension some appear but it’s not entirely clear how to use them all.

I’m fairly certain i2c read register at address at register is broken as looks like it should have two arguments bit it only has one. I put in GH: microsoft/pxt-arcade: i2c read register at address at register block broken #1221 for that bug.