Code block macro disappears when editing the macro like syntax highlighting language on Firefox

Issue Summary

Code block macro disappears when editing the macro like syntax highlighting language on Firefox

Steps to Reproduce

1. Insert code block macro
2. Enter code
3. Double click block heading
4. Change the language (Syntax highlighting)
5. Hit enter
6. Confluence closes the dialog and code block disappears from the page.

Expected Results

Code block macro should change the syntax to highlighted language and should not disappear

Actual Results

Code Block macro disappears

Workaround

The issue does not appears on Chrome browser. It is pertaining to Firefox browser.