Anchor Support on old OSX OS

I’m having an issue with an older version of OSX. OSX 10.6.8, across a range of browsers is causing base characters and accents not aligning correctly. The relevant versions of Chrome being used, when used on a newer OS work as intended, so I’ve narrowed it down to OSX specifically.

Is there any documentation on which versions of OSX do not support mark to mark positioning (for diacritics like â etc)?

Thanks!

I don’t know about that. Could you ask on typedrawers.com?