Roofies? On a drink?

I’d tell the waiter/bar staff/manager immediately.

Tell them what I saw. Discreetly if possible, because I don't know how much access the offender has to them. They need to be in control over what happens after I tell them what I saw, not me.

Tell them there's smth in their drink

Not happening… I’m calling their bullshit out and calling police.

Well first thing is make sure the targeted person does not drink that drink. Then you take that drink and force feed it to the person who did it 😊

I call that shit out, I would never forgive myself otherwise, I would be thinking about that shit eight years later