One big booger

[guero_gordo]

Typically, the only difference between rubbing alcohol and isopropyls is that rubbing alcohol contains more water. To actually sterilize your skin, it has to evaporate more slowly, so they dilute it to 70% vs 99%
If you're really worried about it, use brake cleaner or acetone. Neither will leave a film, but you'll have to be careful not to get them on other plastics

 

[VicHobbyGuy]

If you're really worried about it, use brake cleaner or acetone. Neither will leave a film, but you'll have to be careful not to get them on other plastics

I thought the PEI plate had some sort of plastic coating? I've been over-enthusiastic in the past, using a 'too hot' solvent on a part or finish, so I'd test any solvent on a small corner of the PEI plate. Fortunately the stock Bambu PEI plate that came with my printer is double-sided, so there's a built-in backup.

 

[guero_gordo]

Yah I wouldn't risk it on PEI now that you mention it. I've never needed anything stronger than isopropanol nor have I seen it leave streaks.
On glass, I'm just going to cover it with glue stick anyway, so dish soap is what I've used there