When I am logged into my WordPress site, I encounter a round button with a white diamond in it - what is it?

There is a Siteimprove plugin installed on CAEN Web Publishing and C&M-managed WordPress sites that can help identify accessibility issues, broken links or misspellings, and other content quality concerns directly within the WordPress editor. If you encounter this icon:

in your editing interface (which may be labeled “Siteimprove CMS Plugin” in some interfaces), that means your site has the plugin. You are not required to use the plugin, but it may be helpful in certain instances depending on your editing workflow.