I have been working with WE on a Mac for a week or so and am puzzled by the variability of response times when running the app in the IDE on Chrome.
It started by ProgressBars and Image Well not loading right away. The rest shows immediately, though, but it takes up to ten seconds for these two controls to show. With no real consistency. Sometimes it loads right away, sometimes not. Strangely enough, it seems setting focus to the IDE somehow triggers the display. Apparently, execution is somehow halted as well, and I have a routine that takes between 0.1 second up to 7 as the result. In spite of pragma DisableBackgroundTasks.
Most amazingly, it does not happen at all in Safari, where loading is immediate and consistent.
I suspected extensions, but even after disabling them all, this still happens.
I have not yet tried placing the app on a server, but that is quite annoying. Chrome has many users.