Who is responsible to maintain windows

Recently an owner in our building needed repairs to a window in his unit. The Strata manager told him because the Strata Plan was registered before July 1974 he is responsible for maintenance and cost.

I was always under the impression that Strata Plans registered before July 1974 meant  the owner was responsible for doors to the balcony, however the Owners Corporation was responsible for windows.

Could you please clarify this for me.

Thanks

Slim