I'm a programmer. Or was.
I've used mermaid. Here's a test note
Test mermaid
Want to use mermaid to do sequence and class diagrams.
classDiagram
Class07 .. Class08
Class09 --> C2 : Where am i?
Class09 --* C3
Class09 --|> Class07
Class07 : equals()
Class07 : Object[] elementData
Class08 <--> C2: Cool label
classDiagram
Object .. FontBase
FontBase --> Font
Object --> EventDispatcher
EventDispatcher --> Sprite
Sprite --> Shape
Shape --> TextField
FontBase : layoutText()
TextField : setLayout()
— from Mermaid in Joplin? - #37 by bva
— still doesn’t work - Markdown Guide | Joplin
graph LR
A-->B
A-->C
B-->D
C-->D
but why not just install the Plantuml plugin?
I'm sure the community will sort it out, eventually.