How To Show / Hide Diagnostics Menu Entry

At last moment you got a requirement to disable a particular field on a form. As you tried to navigate to access forms personalization what you see is 

There is no 'Diagnostics' option to navigate to Help -> Diagnostics.

Well the Diagnostics menu entry is controlled by profile option "Hide Diagnostics menu entry"

Navigate to System Administrator -> Profile -> System

Query for your user / responsibility for which you want to provide access.

Set the value at respective level to 

NO = If you want to show Diagnostics menu

YES = If you want to hide Diagnostics menu

Change the responsibility to take the profile option change into effect and try to access diagnostics menu.

Now we are able to see the diagnostics entry.