Screen Got Corrupted For Apparently No Reason

One of my screens got corrupted on an app on the https://code.appinventor.mit.edu site.

AllAboutSpace.aia (3.8 MB)

Q1. Did you login from multiple places at the same time?
A1. No, my collaborator and I are in different time zones altogether.

Q2. Did you paste anything into an Arrangement?
A2. No, and as I've said earlier, nothing happened before it got corrupted.

Q3: What exactly happens?
A3: I can't enter Screen3 at all; it only notifies me that there's an error. I'm not able to view the screen at all. None of the panes open.

Try this one. AllAboutSpace.aia (3.8 MB)

An Dynamic Components extension was missing, do you have any idea about that why?

Did the .aia originate on the ai2.appinventor.mit.edu site then get imported into the code server?

The new blocks are not back-compatible with the code server, which is behind the ai2 server.

Yeah, I used it in Screen2, but deleted it later since it used up a lot of valuable time to load.

Nope, it was coded only on the code.appinventor.mit.edu site.