You are trying to launch insecure content from within a secure site (canvas). Some web browsers may prevent this content from loading.
I get this message when trying to watch the videos from my course.
This happens when a link uses the http protocol instead of the https protocol. Most modern video sites have switched over to https, but it's possible that the video you're watching is still on a site that doesn't support a secure connection, or that the instructor just hasn't updated it (perhaps it was copied from an older course).
I know that what you're describing happens when a teacher adds a link to a non-SSL website in the modules page. Here's an example from my a practice course I have.
If you can open this up in a new window, you should. The gray title bar right under that message should have a title that allows you to open it in a new window. For my example, that would mean clicking on QuestionPress.
You may also let the instructor know that there is an issue and see if they can update their link to a secure connection. If they cannot, then they may want to check the box that says "Open in a new window" when they created the module item so that students don't have to figure out what's going on.
On Mon, Jun 10, 2019 at 9:15 PM firstname.lastname@example.org <email@example.com>
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