Amazing comment in the Copy ][+ source code:

#AppleII #retrocomputing

@a2_4am oh yea!! My favorite kind of fix 🙂
@a2_4am there were a couple versions of the RAMFactor firmware... Wonder if any of them fixed this. I might have to check.
@txgx42 please check! This is the only information I have about the buggy firmware.
@a2_4am I did a search through the available ROM binaries (versions 1.0, 1.1, 1.3, and 1.4) and didn't find anything that looks like 6502 code referencing either zp $19 or #$19
@txgx42 Interesting! Was this an 80s urban legend?