google drive – Gmail Signature Image

When trying to add an image to my Gmail signature, all I see is a broken image placeholder:

enter image description here

When I upload an image, it gets hosted by my Google Drive. When I go to Google Drive I can see that the image is being shared with anyone who has the link (like Gmail). Yet I still get the broken image placeholder.

I can successfully insert an image being hosted by another website, so it appears that there’s an issue pulling the image from Google Drive.

Am I overlooking something here?