Teak oil

If you Google 'how to remove teak oil from glass' you will find instructions for removing it with paint stripper.

A bit of bicarbonate of soda on a damp cloth has a scrubbing action that will break up a film without scratching glass.

Howjado I’ve previously read that WD40 is good for removing oil stains from fabric. It might be worth a try on the glass. It seems to be a product with multiple possible uses.

Try some neat washing up liquid or if you use it bio clothes washing liquid. In the past I’ve cleaned teak furniture and removed excess oil with very dilute white vinegar, that might also be worth a try. Don’t worry, I’m sure you’ll get it off thr glass eventually.

That is the lovely thing about glass, the only thing that damages it is scratches.
I would put a wodge of kitchen paper or a dishcloth/sponge soaked in hot soapy water over it and leave for a while. If it is just an oil then a soapy rub should then be enough.
If it doesn’t budge then it might have a varnish like film which should succumb to white spirit, alcohol, acetone or turps. Just wash each away and dry before trying the next one.
If all else fails then paint remover will work.

You could gently scrape with a blade, this should work.

Try them all, they won’t damage the glass, I got some oil from my kitchen worktops onto the ceramic tile floor and it’s still there!