Need to turn off 2 circuit breakers to turn off fixture
We recently moved into a 1950s home. In trying to replace a fixture, we discovered that in order to turn off the power to it we need to switch off 2 circuit breakers. At least one other fixture is wired this way too. I've never encountered this before.
Is this just how they wired things in the 50s? Is this a safety hazard or just an unusual but safe method? Is it easy to fix? Is it an issue with how the wires are connected to the box or is it the wiring behind the walls?