BrentLeslie-2638 , I have my repro findings:
So I made a dataflow, on a git-enabled Data Factory. Added external call, and wrote some random letters into new mapping. Saved. Reloaded. Then checked the Git repo to see whether it was recorded.
Git view:
UI view after reload:
script view after reload:
So, as we can see, it was recorded, but not loaded properly.
I'm looking now for any related known issues. I have not found any so far.
Since I was able to reproduce the issue I will escalate internally (file a bug report), unless you would like a support ticket?
You mentioned this happened not all the time, but some times? Is this correct? Anything you may have noticed differentiating the two would help pin down the precise cause. Anything from time between save and reload, to expression used in the mapping might help.