DDB Maps
DDB Maps is the VTT inside D&D Beyond.
There is integration with DDB Maps in order to insert map scenes into Foundry very quickly.
It uses the same data that Adventures use, so if we have wall and light information they will be placed.
Some DDB Maps are setup with "Quickplay". This has tokens and stickers already applied to the map, and if they are present you can have DDB Importer use that data.

Auto Grid Aligner
DDB Importer will also try to auto align the grids of maps coming in via DDB Maps using the scaling information and investigating the image to try and find tell tale patterns of grid lines using some clever maths.
You can right click on (any) scene to kick of the grid aligner. Results vary.