Griffpatch's Tower Defense #1520040 doesn't load on Edge

[BryceLTaylor]

If you load project #1520040 on Edge it loads forever. It should match its behaviors on other browsers, where it loads fairly quickly (a few seconds)

Steps to Reproduce

Navigate to the project on Edge https://llk.github.io/scratch-gui/smoke/#15200040
Note: it hangs on the loading screen forever
If you load it on mac chrome it loads just fine.

Operating System and Browser

Edge on Windows

[thisandagain]

/cc @ktbee @kchadha