So this is a problem that probably isn't common, but it's happened to me enough that I get annoyed.

When you open a collection bag, and it gives you options on which item to pick, can we get a confirmation asking if we are sure? When I'm mobile especially, I'll accidentally choose the wrong item. A box asking if we really want that item would be pretty helpful for me.

I agree with this.

There's actually a confirmation box asking if you're sure you want to open the bag itself. This is pretty useless at this stage because it's not like this is an undoable action. When you have the bag and select to open it, you have to confirm, then are brought to the page where you select an item. If you don't want to choose at that moment anymore, you can just leave the page with no consequence. The confirmation would be better suited for when you actually choose an item, which can't be undone if you misclick.