I noticed this error as well but initially ignored as it wasn’t marked “Fatal” but was concerned it may cause packaging issues for me. Just tested this and at least for me (an existing project) I was able to package without issue. I am not using VR in my game and was sure to look at the plugins, search for VR and ensure that all of them were turned off (which they were).
This bug was definitely introduced in 5.0.3 as this error was not occurring in 5.0.2 and I can see that pack file was recently updated. I don’t think you can edit this without a source build as a “upack” file is binary and similar to a zip file but also introduces compression and is a custom format. Is there any existing issue to track?