sequence diagram: multiple messages / multiple notes on same line

[GavinPen]

PlantUML sequence diagrams (see https://plantuml.com/sequence-diagram) allow:

• multiple notes on the same line, eg:
  @startuml
  note over Alice : initial state of Alice
  / note over Bob : initial state of Bob
  Bob -> Alice : hello
  @enduml

• multiple arrows on the same line (parallel messages), eg:
  @startuml
  !pragma teoz true
  Alice -> Bob : hello
  & Bob -> Charlie : hi
  @enduml

But d2lang doesn't seem to allow this.

Could this functionality be added?