I am trying to import a production workflow export (.nwf file) over top of a test environment version. I opened the test workflow in edit mode and clicked the ribbon icon to import. I selected the export from production. It shows an empty workflow - nothing between the start and stop nodes in the IDE.
I found a previous topic for this, but the answer marked as a solution was basically akin to waiting for magic to happen. I refuse to accept that as an answer.
My .nwf backup file is a mere 94 KB in size.
I performed the export and import twice, with the same results both times.
It is possible this is related to a problem we had many months ago, which was never resolved. I had been deploying workflow changes across multiple sites and libraries using PowerShell. That process suddenly stopped working. I only had a few workflows to deploy at that time, so I did it manually (using this same export/import process). The problem was never resolved because it was no longer at the top of my priority list. But with this new problem of not being able to do it manually, it has now escalated.
So I found a solution - use Internet Explorer.
In both Edge and Chrome, I tried two different ways to import. I opened the existing workflow, went into Edit mode, and then tried to import the .nwf file over top. Then I tried to create a new workflow and then import to that. In both cases, with both browsers, it's like the import process did absolutely nothing.
In IE, the import succeeded over top of the existing workflow. It's a shame we have to use the old technology.