Love the comments:

"7/27/78 FIXED BUG WHERE FOR VARIABLE AT BYTE FF MATCHED RETURN SEARCHING FOR GOSUB ENTRY ON STACK IN FNDFOR CALL BY CHANGING STA FORPNT TO STA FORPNT+1. THIS IS A SERIOUS BUG IN ALL VERSIONS."

Not far off from a comment I might make these days

https://github.com/microsoft/BASIC-M6502/blob/main/m6502.asm...