Supposing you've added a new custom template for a core block type, such as "page_list", when you've added this to the page you're then getting a "view.css - 404 not found" log in the browser console.
It's then trying to load:
The reason is because of a small bug in Concrete5 5.7. If you add your custom templates in the following format:
Then you'll encounter this issue. However if you add them in the more self-contained format:
Then it won't try to load the base view.css and throw the 404.
Hope this helps.
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