If you’re an administrator of a SharePoint Online site and you want to make sure that your content stays online, the right way to do it is to use Page Diagnostics for SharePoint. This tool is a performance monitoring and diagnostics tool for SharePoint sites. It will scan your site and detect any performance problems and suggest how to solve them.

Page Diagnostics for SharePoint Online consists of the following sections:

• The Attention Required section: This section consists of all of the issues that require immediate attention.
• The Improvement Opportunities section: If the issue can be solved with a simple improvement, it is going to be included in this section.
• The No Action Required section: If the issue is not going to affect the performance of your site, it is going to be included in this section.