Home built 1921 but complete electrical upgrade less than 20 years ago. White corrosion looking material coming out of the breakers. I would write up as corrosion and move on but it is completely uniform across all breakers in the panel in the exact same place. Just looking to understand what it is for future reference.
And there you have it! Thanks man! The uniformity is what made me think it was something that was supposed to be there but I just hadn’t seen anything like it before.