Hi @Pick_ViT0
Your question is probably better asked here: jgraph/drawio · Discussions · GitHub
The app for integrating draw.io with Nextcloud is maintained by JGraph Ltd, the company behind draw.io, and as far as I know, it doesn’t change anything in draw.io itself. So if there is a way to change the color scheme, the relevant settings would have to be found somewhere in draw.io.
