Cloudflare tunnel generates dangerous site warnings from Google

I created a Zero Trust tunnel and application/policy for it. It all worked as expected, allowing me to access my local machine via ssh-in-browser. However, a few days later, Chrome/Google began marking my site as dangerous with a big red warning and extra click to proceed to the site. Why is this warning appearing?

Is the warning expected given that Cloudflare tunnel is in fact a man-in-the-middle of my secure connection to my site?

What are the steps to confirm there are no issues and remove this warning?

I’m also getting false-flagged by Google on several (but not all) of my tunnels. The only option I can see is to report it to Google as false from the “Let us know” link under Details.

It would be swell if Cloudflare and Google could put their heads together and figure out why this is happening.