Performance issue when opening a document

[dfmedrano (Jorge)]

This topic comes from the orignal report found here

@Cux

This is mine activity monitor, on a project with 3 pages and like 25 artboards around 50 symbols few big images…every 15/20 minutes sketch became unresponsive for like 10/15 seconds, plus in a random mode when i focus out for example i go on the web browser or in photoshop, again i have to wait like 10/15 seconds to get back in Sketch. For me it’s not a matter of time, the problems appear immediately upon opening, and randomly throughout the entire working process on the file