Couple of points: 1. If a bag is resealable, then it must have been sealed in the first place
2. If you read far enough on the
official Stanstead site, you will find "
Security FAQs" and at the very end it says - (my emphasis)
Security control
What do I need to do with my transparent resealable bag?
Have it ready for inspection at security. Ensure it is fastened closed and kept separate to your hand luggage...
Rest of BS snipped.