Anchor macro broke editor when users use "Enter" button to save the macro

Summary of The Bug

Anchor macro broke 4.0 editor when users try to edit the anchor inside the lowest cell and save their modification by pressing "Enter" on Safari browser. This would result to broken editor as in "Preview", "Save" and "cancel" button is not working.

How to reproduce

1. Access Confluence using Safari browser
2. Create a new page
3. Create a 2x2 table
4. Add an anchor on the first row
   
5. Create a new anchor, and save it using enter button
6. Anchor is not saved and editor is freeze