Groovy Macro Content field appears to be mandatory only on CKEditor UI edit mode

STEPS TO REPRODUCE

1. Edit a page in CKEditor mode
2. Click on Insert > Other Macros > Groovy
3. Click 'Submit' without filling the content
4. Go to Source
5. Paste 

   {{groovy}}{{/groovy}}

1. Click on Source again
2. Save the page

EXPECTED RESULTS

In CKEditor edit mode as well as editing the page in Source mode, the Content field is mandatory.

ACTUAL RESULTS

In CKEditor edit mode if the content it's empty (UI box), the Macro cannot be submitted into the page, but when inserting the macro from Source, it's being inserted with no content.