Number 2, palettes. As you can see, I can use the first palette just fine. Then I switch to the test palette and nothing works. I press the button to add a new color dozens of times. If there were colors in there, I couldn't open their context menus either. I switch back and things work there.
I'm bored, so here's a video to show what is broken in Affinity V3. The layer with the orange marking is a symbol, meaning that it can be used in multiple places and any changes are automatically synchronized. This works at first. Then I copy the layer and delete the original. Now it's broken. Normally, if a symbol gets detached (i.e. the synchronization is broken), it's marked with a dashed orange line. This isn't the case here, and copying such layers shouldn't detach them anyway. So I can't edit any of my drawings now without worrying about breaking them like this.