You previewed your WordPress site and almost everything was broken. What the heck?
WordPress uses full URLs (instead of relative paths) for your style sheets (CSS), as well as links to your posts and images. When you preview your site, you're using a domain other than your primary domain, so none of those links work. Without working resources your WordPress site looks like it's broken.
Fortunately, this doesn't mean anything actually is broken — just that it's not working the way you're viewing it.
The simplest way to resolve the issue is to preview your website by modifying your computer's host file. The steps are a little complicated, but we have them available for you in Preview your website using hosts files.
If you somehow started developing your site using the preview URL, you can use the Search and Replace plugin to find all instances of the preview URL and replace them with your actual domain.
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