Custom procedure definition (and corresponding substack) disappears with uncaught error

[kchadha]

Expected Behavior

Blocks should not disappear from workspace.

Actual Behavior

Custom procedure definition disappears with the following error in the console:

Uncaught Trying to replace a shadow on a custom procedure definition.

Steps to Reproduce

Not sure how it happened (needs repro). Circumstances involved in producing the error:

• adding a bunch of blocks to the workspace of a sprite
• adding a new sprite via the sprite library
• switching back to the original sprite immediately after adding the new sprite (and then the custom procedure definition was gone)

[BryceLTaylor]

I can't seem to reproduce this. Do you have any other info about how it comes up? Are you adding a bunch of blocks to the custom procedure, or just randomly on the workspace. Is there a particular sprite that you've added to get the error?

[kchadha]

@BryceLTaylor Unfortunately I don't have much more information. I was trying to add a lot of blocks to the workspace (not in any sensible order necessarily) for testing save and load. I did create a long stack with my custom procedure, and I think I was just working on the cat sprite.

[ericrosenbaum]

I think found a repro for this!

• create a custom block
• use a c-block to kind of grab the fake block inside the custom block definition hat
• add some other blocks
• switch to another tab and back... blocks have disappeared!

[kchadha]

Fixed in scratchfoundation/scratch-blocks#1751. CC/ @BryceLTaylor