Find and replace for symbol instances! It's a royal pain to swap all instances of one symbol with another. Layer filters don't allow shift-click bulk selection across multiple nested groups.

I like the concept, but it's pretty buggy. At least for me, with multiple monitors... it looks good one my primary monitor, but the menu bar on the secondary monitor is missing the < icon, and there's a "ghost" menu bar on my primary monitor.

Yup, I've been experiencing duplicate symbols. However, I didn't notice this was occurring as it was happening — I noticed all the duplicates in my file after designing for a day. Have you found a pattern? I'm not sure exactly which action is causing Sketch to duplicate symbols (copying and pasting a symbol in my design did not recreate the issue).