The issue is actually caused by mai_get_image_src_srcset_sizes calling wp_calculate_image_sizes during the preload of featured/logo/images.
So far, it looks like calling get_queried_object_id() makes sure we get the actual single post ID and not the ID from inside the loop in Mai Post Grid.
This took forever to find and is related to this commit https://github.com/maithemewp/mai-engine/commit/a570d015ba52755d5e6dada187c8b90acbc80e47, though it turns out that isn't a solid fix.
The issue is actually caused by
mai_get_image_src_srcset_sizes
callingwp_calculate_image_sizes
during the preload of featured/logo/images.So far, it looks like calling
get_queried_object_id()
makes sure we get the actual single post ID and not the ID from inside the loop in Mai Post Grid.