I apologize in advance - this is going to be a vague report. I can't share a capx as it only happens with large projects.
Steps to reproduce:
Basically, after a short time in the editor, the editor seems to slow down, both in layout and event sheet view. All my layouts have 11 layers, and when I do an action in the event sheet (Not all clicks, just add action, move stuff, undo, redo, etc), I see a really weird sequence where my layers appear to shuffle themselves randomly for a few seconds. They don't stay out of order or anything, but it slows the editor noticeably.
The issue has been happening for a while. I think it may have originated with the update where layouts were associated with event sheets for smart layout launching, but I'm not sure.
Internet Explorer: N/A
Operating system & service pack:
Construct 2 version: