Saving sometimes hangs on Edge for vector costume containing a large bitmap

[ericrosenbaum]

Expected Behavior

Saving should complete!

Actual Behavior

Sometimes, the "saving project..." spinner in the menu bar hangs indefinitely, on Edge, for projects with a vector costume containing a large bitmap.

Steps to Reproduce

• Use Microsoft Edge (maybe on a slow-ish computer?)
• Create a large bitmap image costume e.g. using use the "camera" option to take a picture with the webcam
• Press the "Convert to Vector" button
• Download the sb3 file
• Press File->new
• Upload the sb3 file
• "Saving project..." may hang indefinitely (if not, try uploading the sb3 file again)

Operating System and Browser

Windows 10 v1903
Edge 87.0

[BryceLTaylor]

I was unable to reproduce this using the same project as @ericrosenbaum on a very similar computer. I'm not sure why. Eric could reproduce it with some frequency, if not regularity.

[chrisgarrity]

I've added "needs repro" since we are not able to reproduce this consistently. I'm not marking it "help wanted", but if anyone wanted to work on documenting a consistent way to reproduce the problem, that would be helpful.