The canonical URL is now being correctly passed by the CMS and is also properly output in the meta tags.
However, it looks like the same was unfortunately forgotten for the Open Graph meta tags.
There, the correct blog URL is still not being output.
Sorry for my enthusiasm — and for possibly being a little too good at finding little things 
I already have that enabled. When activated, it does get output — but further down in a separate section.
The problem is that the Open Graph meta tags then appear twice in the header.
Once with the correct URL and once with the wrong one, with the incorrect URL appearing first.
See the screenshots. I don’t think that’s a particularly optimal solution.
