I have an SPO Communication site with three custom site columns (all Managed Metadata type) which are all in two separate custom content types. the site columns are mapped to RefinableString00, 01, and 02.
When I add the first content type to a custom list, I can then add a Highlighted Content web part to match items in the list on the managed metadata properties. In Content, my Source is This Site, Type is All, and Document type is Any. In Filter and sort, I Filter a Managed property, search for RefinableString00, and type what the term I want to match is (Contains). Items return from the list as expected but not from Site Pages
I have the second content type added to my Pages library with pages with all three columns populated. I tried targeting the Pages library specifically by setting Source to The page library on this site. However, doesn't look like managed metadata works with the page properties.
I also tried setting Source to This site and Type to Pages. When I type the refinable to find the managed property, nothing populates.