Comment 3 for bug 1514641

Hm, that could be it. I think when you copy a page, in some cases it continues to point to the original artefacts instead of giving you a copy. (Specifically, some of the blog blocks can do this.) If that's the case, then perhaps there's a bug in the institution page delete code that fails to clean up those links.

So, probably best to fix it on both sides. Correct the code that is failing to delete the link, and change the BlockInstance rendering methods to be more robust against missing artefacts.

By the way, is that an actual error that crashes the page and makes it impossible to edit the block? Or is it just a warning message in the logs?

Cheers,
Aaron