JS does WHAT!! 
Thank goodness someone has come to their senses. I started programming in Fortran, learnt Cobol and Pascal (showing my age). Coded in assembler on PDP11/04 (and many other machines and chips since) but never heard of a language that assumed something that started with a zero to be Octal. (Said i was a novice in JS and I think I might just keep it that way 
)
I referred to JS documentation but did not realise there are significant differences in the versions. So thanks for the feedback, it’s most appreciated.
@Paul_Stewart, let us know how you get on.