No-Arrow Edges
Lines without arrowheads: solid `---`, dotted `-.-`, thick `===`.
no-arrow-edges.mmd
graph TD
A[Node 1] ---|related| B[Node 2]
B -.- C[Node 3]
C === D[Node 4]graph TD
A[Node 1] ---|related| B[Node 2]
B -.- C[Node 3]
C === D[Node 4]