The page was reloaded, because the character encoding declaration of the HTML document was not found when prescanning the first 1024 bytes of the file. The encoding declaration needs to be moved to be within the first 1024 bytes of the file.
example_computer.html:41
MAME exception: Unknown slot option '""' in slot 'sl4'
loader.js:1123:42
Attempting to fall into debugger
loader.js:1123:42
exception thrown: 9282648
mameapple2e.js:1:3016211
Successfully compiled asm.js code (loaded from cache in 127ms)
mameapple2e.js
uncaught exception: 9282648