ServiceNow Notifications allow you effectively and efficiently implement email notifications. We use email notifications to send selected users email about specific activities in the system, such as updates to incidents or change requests. I will show the results of my testing with the 'Sys version' and the 'content type' options. Both configurations change the message sent behavior.

Email Notifications 'Sys version' and 'Content type' fields

Here is how it looks on the email notification table:

After performing some test by setting and changing the Sys Version, content type, Message, 'Message HTML' and 'Message Text' and reviewing the Email notification sent, find my results below:

With Sys Version V2 set, the followings are the results:

Notification	N1	N2	N3	N 3
Content Type	HTML+PLAIN	HTML+PLAIN	HTML+PLAIN	HTML+PLAIN
Sys Version	V2	V2	V2	V2
Message (M)	-no effect-	-no effect-	-no effect-	-no effect-
Message HTML (MH)	MH	MH	-blank-	-blank-
Message Text (MT)	MT	-blank-	MT	-blank-
EMAIL RESULT
Body	MH	MH	MT*escaped	watermark
Body Text	MT	MH*stripped	MT	watermark
Context Type	multipart	multipart	multipart	multipart
…
Notification	N5	N6	N7	N8
Content Type	HTML only	HTML only	HTML only	HTML only
Sys Version	V2	V2	V2	V2
Message (M)	-no effect-	-no effect-	-no effect-	-no effect-
Message HTML (MH)	MH	MH	-blank-	-blank-
Message Text (MT)	MT	-blank-	MT	-blank-
EMAIL RESULT
Body	MH	MH	MT*escaped	watermark
Body Text	-blank-	-blank-	-blank-	watermark
Context Type	text/html	text/html	text/html	text/html
…
Notification	N9	N10	N11	N12
Content Type	Plain Only	Plain Only	Plain Only	Plain Only
Sys Version	V2	V2	V2	V2
Message (M)	-no effect-	-no effect-	-no effect-	-no effect-
Message HTML (MH)	MH	MH	-blank-	-blank-
Message Text (MT)	MT	-blank-	MT	-blank-
EMAIL RESULT
Body	-blank-	-blank-	-blank-	watermark
Body Text	MT	MH*stripped	MT	watermark
Context Type	text/plain	text/plain	text/plain	text/plain

Sys Version V2 do not uses the Message field. Instead it uses Message HTML or Message Text fields based on the Content Type selected

With Sys Version V1 and -none- set, the followings are the results:

Notification	N13	N14	N15	N16	N17	N18
Content Type	HTML+PLAIN	HTML+PLAIN	HTML only	HTML only	Plain Only	Plain Only
Sys Version	None/V1	None/V1	None/V1	None/V1	None/V1	None/V1
Message (M)	M	-blank-	M	-blank-	M	-blank-
Message HTML (MH)	-no effect-	-no effect-	-no effect-	-no effect-	-no effect-	-no effect-
Message Text (MT)	-no effect-	-no effect-	-no effect-	-no effect-	-no effect-	-no effect-
EMAIL RESULT
Body	M	watermark	M	watermark	-blank-	watermark
Body Text	M*stripped	watermark	-blank-	watermark	M*stripped	watermark
Context Type	multipart	multipart	text/html	text/html	text/plain	text/plain

• MH*striped means that the HTML tags are removed. String fields inside ARE NOT stripped. HTML fields get stripped as well.
• MT*escaped means that any HTML inside are escaped to HTML (e.g > translated to >). HTML fields inside are NOT escaped.
• M*stripped means that any HTML tag inside is removed*.

Sys Version V1 or -none- do not uses the Message HTML or Message Text fields. Instead it uses Message field.

As you can see, Sys Version controls whether Message or Message HTM/Text is used.

Here is how it looks messages with Sys Version = V1 and Content type = HTML+Plain:

Sys Version, Content type, Message, and Message HTML on Email Notifications

Here are a few fields on the Email Notification form (sysevent_email_action):

Email Notifications
'Sys version' (sys_version):	It indicates which notification version is used. On Fuji, sys_version can be none,"V1" or "V2". V2 is the default
'Content type' (content_type):	It contains the type of email notification to be sent. It can be HTML and plain text, HTML only or Plain text only.
'Message' (message):	It contains a max 4000-char string* (it can contain mail script) that will be part of the output notification. When sys_version = "V2", this field is ignored.
'Message HTML' (message_html) and 'Message Text' (message_text):	It contains a max 4000-char string*(it can contain mail script) that will be part of the output notification. When sys_version = "V1" or -none-, these fields are ignored.

Content type, Body and Body text field on the email table

Here are a few fields on the outbound Email (sys_email):

Outbound emails
Content type (content_type):	It is a string that identifies the content type of the email.
Body (body):	It is a 8000 string that contains HTML compatible text that will be part of the outbound email. HTML email needs to be properly coded. HTML lets you include your logo or brand colors to provide a professional look and make your emails quickly recognizable. Used for "multipart/mixed" or "text/html" mail
Body text (body_text):	It is a 8000 string plain text. It is exactly a text-only format. Any device and email service provider displays plain text well. Used on "multipart/mixed" or "text/plain" mail

Conclusion

Email notification option Sys Version empty or V1 makes notifications to use Message, whether Sys Version V2 makes notification to use Message HTM or Message Text according to the content type set.

More information can be found here:

NOTE: Tested in Fuji, using Chrome