GHE Mermaid Diagrams Unable to Render

[Ryanflex2003]

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I am on the understanding that GHE supports mermaid diagrams as of GHES 3.7. My companies cloud org is currently on GHES 3.7.4 (says in the bottom left of main landing page), however writing mermaid in markdown in GHES 3.7.4 is returning back an Unable to render code block.

For Example. I can write something simplistic such as below and this works here AND on my personal public repository, but not in my companies GHES which is on 3.7.4:

graph TD
A-->B

Loading

Instead I return the below. Any ideas to why? In fact, I retrieve the same result back using any of the diagrams in markdown that say they are available in 3.7 Github docs that should be available for enterprise 3.7. Is something wrong specifically in 3.7.4 or is there a setting that could be disabling these?