Mermaid 12: edge targeting a subgraph ID now renders without TypeError (fix verification)

In the Mermaid Live Editor, the user demonstrates and verifies the rendering behavior for edges targeting subgraph identifiers in Mermaid v12. Starting with the default flowchart template, the user selects the code editor, replaces the existing script by selecting all text and pasting new flowchart code between [4.4s] and [5.3s].

Upon pasting, the live canvas immediately re-renders the updated diagram without errors, displaying a nested subgraph structure alongside a green confirmation banner stating "Renders OK on Mermaid 12 · 20 elements" at [8.6s]–[13.0s]. At [10.0s], the user clicks the "Reset view" button on the diagram canvas toolbar and inspects the visual elements. The user then clicks the "Zoom in" button at [22.0s] and [23.0s] to enlarge the canvas.

Finally, at [30.8s]–[30.9s], the user clicks back into the code editor and navigates to the top of the file. This reveals the Mermaid syntax demonstrating edges directly connecting node Decision to subgraph IDs ThenSequence and ElseSequence without triggering type errors.