It’s been a while since I’ve been but the glass thing was mostly around glass bottles and the like. I definitely had a compact mirror for my make up. They didn’t check that much anyway.
I’m a wine drinker and took the boxes of wine instead of bottles, but I saw some plastic bottled wine in Tesco yesterday. You’ll struggle to get ice unless you’re buying drinks from a vendor - it’s a place where you need to get used to warm drinks and unsanitary conditions 😂
We didn’t take much/any food the first time but subsequent times took a one burner stove and had some pasta etc. mostly because the food is expensive but I was also hungover or drunk 95% of the time and it was good to have access to noodles and a cup of tea! Also take plenty of snacks, so you’re not always having to have meals.
We couldn’t ever shower and the taps are obviously cold so you need to get those big body wet wipes they use for bed bound people, plenty of dry shampoo, pocket tissues in spades (to double up as toilet roll), hand sanitiser.
Try and make your tent as comfy as possible - proper pillows etc. don’t bother with a blow up bed, they are rubbish in my experience. Take ear plugs and eye masks. Chuck in some battery powered fairy lights for ambience!
Also don’t buy a tent from Tesco, Argos, or any supermarket/popular retailers - everybody else will have the same and it’s hard to find them in the dark - also some identifying flag/bunting etc. helps.
Take extra batteries or similar for your torches - have a mag light in your bag to help you get back to your tent. A couple of lighters for camping stove.
You’ll have a great time! Just embrace being a scuzzy hippy for a few days.
edited to add that we were only a couple of years from having a 3310 when we went so charging phones wasn’t much of a thing and they’d have charging tents. Assuming people take solar power banks these days?