Using Chrome to inspect my beta sight, I see these two errors at the bottom of the console...
DevTools failed to parse SourceMap: http://...com/combine/bootstrap.min.css.map
DevTools failed to parse SourceMap: http://...com/combine/shuffle.min.js.map
Is this a problem or is this normal? Does it affect performance?
In my opinion, you uploaded that plugins using the backend upload feature. Unfortunately, the backend upload feature can't upload .map file, so it uploaded only css, js and images.
The solution would be to upload the missing files using a FTP software, or to create a PR to the october core in order to accept upload of .map files.
I would prefer the second solution as it's quite annoying to not be able to upload .map file in your theme assets.
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