I’m experiencing the same issue. The project was running smoothly until we upgraded from version 5.2 to 5.3. I’ve attempted various solutions to address this problem. For instance, I wrote a script to reload all the blueprints in the project. After executing this script, the game functions correctly. But, as you’ve mentioned, if I restart the editor, all the nodes disappear again. I also tried resaving all the files in the project after reloading all assets, but this didn’t resolve the issue either.
The problem seems related to the references or something similar. I might be mistaken, but when I reload a blueprint exhibiting this issue and then duplicate it, saving and restarting the editor retains the node in the duplicated version. However, when I then use the “replace references” feature to switch from the old asset to the new one and then restart the editor, the node disappears from the duplicated version!
I’m really interested in finding a solution to this problem. It seems like it affects the Enhanced Input nodes only of what I have seen. As a workaround, we might need to handle all input binding in C++. However, it feels a bit unstable. I’m not sure if it’s only the Enhanced Input nodes that are affected. Could the blueprints be corrupted? Is there an issue with loading references? I can’t tell if the problem is just with the Enhanced Input system or not.
Here are more people having this issue:
https://forums.unrealengine.com/t/ue5-3-bug-enhanced-input-bindings-in-blueprints-dissappear-when-re-opening-the-project/1296888