Wikimedia Bugzilla is closed!

The text "<jsondata-invalidjson>" appears above the HTML textarea on test2.wikipedia.org when attempting to save an invalid JSON Schema.

Steps to reproduce:

1. Go to <https://test2.wikipedia.org/w/index.php?title=Schema:HELLO&action=edit>.

2. Enter "abc" into the textarea and press "Save page".

3. Observe the area above the textarea post-submission. The user ends up at a URL such as <https://test2.wikipedia.org/w/index.php?title=Schema:HELLO&action=submit> and the top of the page reads:

---
Creating Schema:HELLO
<jsondata-invalidjson>
---

Might be localisation cache? Dunno.