Report: flag browser performance is terrible

[JonnyOThan]

This is mostly a note to myself. I have a DM from someone with profiling data but I haven't looked into it yet.

[Phantomical]

Here's what the flag browser looks like when scrolling through the flags with multiple flag packs installed (from a user-provided profile)

I suspect the answer here is going to be to use a virtual list uGUI component like this one: https://github.com/disruptorbeaminc/VirtualList