On my local MediaWiki installation, the "Edit pages on double click" preference causes a really bad behavior. This is not seen in production, so it could just be me or could be interaction with another feature. I'll try to figure that part out and will report back here.
Steps to reproduce:
- Enable "Edit pages on double click"
- Double-click anywhere on an article page, from any view including the history list or conflict workflow.
Result: You're navigated to a full-page editing interface.