Issue with flow diagram become corrupt

I made a reasonably complex flow and copied it then renamed and moved the flow to another folder. I began working on it and changed a bunch of pieces and then when I scrolled down the flow diagram is corrupt. I have seen this twice now as I was able to reproduce it again but not consistently.

Is this a known issue?

To get rid of the issue I had to delete most of the modules.

There is no mechanism for upload an exported flow so can’t add that here.

I can now reproduce this, but I’m not sure this is the only reason it happens.
Some actions in Active pieces such as duplicate create a new tab at least in chrome anyway. I had the same flow open in two tabs and inadvertantly changed one and then went back to the other tab and change it there. Because there is nothing like a MVC model the other UI does not reflect the change and you now have one flow with two views and they are out of sync.

Propose that if the flow is being edited then you can only open a read only version in another tab.

How do you know it’s being edited in a web based UI?
You would have to set a flag and expire the UI if no actions are taken within a certain timeframe.