What's new in Music Connect?
April 8th, 2020
In the Add Albums from Core screen, it was already possible to select multiple 1-disc search results and add them together as one multi-disc albums. But, as of today, you can also merge existing albums in your database into a multi-disc album.
Just select them in your list with the checkboxes, then select Merge Albums from the blue Action bar.
See this feature in action here: