Multisite using Stargazer

I am working with a WordPress multisite client that uses the “Stargazer” theme v4.0.0 for two of the mutisite nodes. On both of these sub-sites, we are seeing a PHP Warning message:

“Warning: Invalid argument supplied for foreach() in /srv/users/peterbrice/apps/rural-transit-com/public/wp-includes/class-wp-theme-json.php on line 1091”

Though this message does not directly implicate the “Stargazer” theme, I’ve found that if I apply this theme to other nodes of the multisite, then they start displaying this Warning message too.

So if you could please look into this, hopefully there is an easy fix.