Currently gitGraph only supports horizontal graphs in Obsidian. I have a very long graph that I want to render vertically, but I can’t because Obsidian’s mermaid version doesn’t support it yet.
I agree that upgrading mermaid to the latest would be good. Beware though that some of the new diagram types are experimental with few configuration options and don’t really look very good. A case in point is the mindmap diagram type with looks awful IMO. I’ve added a picture of a mind map I created using this diagram type in the mermaid live editor for a project I am working on. There is no programmatic way to specify the layout option to stop the nodes overlapping.
The best option was to use the Mind Map plugin which doesn’t let you edit the contents but does produce a nice looking map that i use now as an alternative to the TOC.