After upgrade, images do not display

Upgrading my laptop, and Mattermost, seems to have broken the ability for Mattermost to display images inline in threads.

Pre-upgrade, I was on a Macbook Pro running Monterey (12.6.3) and Mattermost 5.0.2. Post-upgrade, I am on a Macbook Pro running Ventura (13.3.1) and Mattermost 5.3.1.

The image below shows the pre- and post-upgrade display (I’d like to have broken this into two images, but new users can only embed a single image :/…).

I can find no property or setting that overcomes this. Other forum posts with similar problems seem to be for Linux systems where there is a direct image download directory (like /opt/mattermost/data); there is no such equivalent directory (that I can find) for image download on a Mac.