Matrix is a secure site, and users' connections to our Matrix site are secure.
Depending on what page you are on within Matrix, your browser may indicate that the page is not secure. The reason this happens is that, in order for a browser to say that a page is secure, 100% of the content on that page has to be secure (https). If there is a single link or image on that page that links to a site that is not https, the browser will say that the whole page is not secure.
For instance, there are a handful of links in the External Links widget on the Matrix homepage that go to sites that are not https. Therefore, according to the way browsers see that page, it is not a secure page. Since we cannot control whether or not a site we link to (Listingbook, RPR, etc.) is an https site, there is nothing we can do about this.
You can be assured, though, that all computers' connection to Matrix is secure, and that the overwhelming majority of pages within Matrix are secure. The only parts that can be (loosely) considered not secure are links to other websites or images (such as those in News & Alerts articles) that are housed on pages that are not https.