In this project here, you can see what I mean: https://scratch.mit.edu/projects/278950351/ No longer shared.

The custom block input has a large white editable and removable piece in it instead of a regular input. I don't know how it was created, but I think it appeared after reloading the project. I was editing normally at the time. The JSON for original project had been edited in 2.0, but I since removed the hacks and they were in a different sprite. More information can be found in the notes of the project above.

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