Excercise feedback window takes multiple seconds to load

[ljleppan]

The exercise feedback window (shown after all tests pass on server) takes multiple seconds to load on a high-end PC running Windows 10. During the loading, the system is completely unresponsive.

The window seems to load to a stage where only the yellow smiley is missing, then hang for a few seconds, displays the smiley and then works fine.

Not a huge issue, but makes the program annoying to use.

[nygrenh]

This is a duplicate of #148

[ljleppan]

Thanks, closing this as a duplicate.