How do I get rid of this adhesive residue?

[NirvanaFan]

Just bought a flat and the old owners were obsessed with stick on everything, with the worst offenders being stick on mirrors in the bathroom.

I used a hairdryer and scraped off what I could but there is still these square marks of residue. If I try and scrape them any further I reach the green part underneath that you can see. I've tried painting over a couple with Zinsser 123 to see what it looked like but you can see it still shows through.

Any advice?

 

[Wayners]

Multisolve.

Toolstation. B&Q and many other places sell.

Works quickly although stubborn glues give it a minute

 

[NirvanaFan]

Multisolve.

Toolstation. B&Q and many other places sell.

Works quickly although stubborn glues give it a minute

Thank you, I'll give this a bash and see how it goes.