This works for both Blueprints from the Axiom Mod and Litematica schematics, as they both embed a preview image in their respective formats.
This plugin requires creating custom file associations. I couldn’t find any publically coordinated convention, so I used the mimetypes model/prs.axiom.blueprint and model/prs.litematica.litematic. The README has instructions for this.
I would recommend you to add a mimetype for the files at
There is the start of the work for some of minecraft file:
So user don’t have to install this mimetype.
For specific applications files, the convention is to use application/x-application-...
Here probably application/x-minecraft-model-axiom or something.