JiBrok, message field, JavaScript Example: The script will check the custom fields on the view issue screen. If all fields are empty, the message banner will be hidden.

hide message if all fields are empty(View issue).js

function checkFieldsAreEmptyAndHideMessage(fieldIds, messageFieldId){
 	AJS.$.ajax({
            url: AJS.contextPath() + '/rest/api/2/issue/' + JIRA.Issue.getIssueId() + "?fields=" + fieldIds.join(),
            type: "GET",
            async: false,
            success: function(issue) {
            	if(areAllFieldsEmpty(issue, fieldIds)){
            		hideMessage(messageFieldId)
            	}
            }
        });
}
 
 function hideMessage(messageFieldId){
 	AJS.$("#rowFor" + messageFieldId).hide()
 }

 function areAllFieldsEmpty(issue, fieldIds){
 	for(var i = 0; i < fieldIds.length; i++){
		var fieldId = fieldIds[i]
		if(issue.fields[fieldId] != null){
			return false
		}
	}
	return true
 }


//The script will check the custom fields on the view issue screen. If all fields are empty, the message banner will be hidden.
if(JIBROK_MESSAGE_FIELD_CONTEXT == "VIEW_ISSUE"){//version 3.1.7+ or set JavaScript context - Issue view screen
	var customFieldIds = ["customfield_10201", "customfield_10202"]//fields will be check on null value
	var messageFieldId = "customfield_10013"
	checkFieldsAreEmptyAndHideMessage(customFieldIds, messageFieldId)
}