See also the official documentation:

• Help Center > Members Manual > Additional information > Understanding message footers
• Help Center > Members Manual > Additional information > Understanding message digests

Your Friend, the Footer

If you receive messages from a group via email you've no doubt noticed that block of stuff at the bottom of each message. That's called a message "footer". If you read group messages on the Messages pages of the group you won't see these footers.

Note: Although both appear at the bottom of messages, footers are different from signatures, or sig-lines. Signatures are written by and specific to individual senders. The Groups.io message footers are added by the system and are not under an individual's control.

The format of the footer depends on the the type of message. It varies between formatted (HTML) versus unformatted (plain text) messages, and it is different for individual messages versus digests of messages.

Formatted (HTML) Individual Message

You receive all messages sent to this group: This text reflects your Message Selection setting, under Advanced Preferences in your Subscription page. Muted threads or hashtags not included. The alternate text is "Every message in topics or hashtags you are following is emailed to you." and optionally
"The first message of every new thread is also emailed to you."

View/Reply Online: This is a link to the message, shown in the group's Messages section. The number that follows is the message number.

Reply to Group: This is a mailto: link — it causes your email interface to open a new message composition window, directed to the group's posting address. The new message will have the Subject line filled in, but will not contain a quote of the original (for that use Reply online). Note that proper functioning of this link is subject to the capabilities of your email interface and possibly to the settings in your operating system (default email client application).

Reply to Sender: This is a mailto: link — it causes your email interface to open a new message composition window, directed to the sender's address. The new message will have the Subject line filled in, but will not contain a quote of the original (for that use Reply online). Note that proper functioning of this link is subject to the capabilities of your email interface and possibly to the settings in your operating system (default email client application).

Mute This Topic: This is a link to a page which will Mute this topic so that you do not receive further messages (by email) in this topic. See the Help page for more information on Muting and Following topics.

Follow This Topic: [not shown] This is a link to a page which will Follow this topic so that you receive further messages (by email) in this topic. This will only be seen if you have selected Following Only and First Message Also in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Unfollow This Topic: [not shown] This is a link to a page which will unfollow this topic so that you do not receive further messages (by email) in this topic. This will only be seen if you have selected Following Only in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

New Topic: This is a link to the New Topic page in this group.

Mute #hashtag: This is a link to a page which will Mute the named hashtag so that you do not receive further messages (by email) that have this hashtag. If there is more than one hashtag on this topic there will be a link for each. See the Help page for more information on Muting and Following hashtags.

Group-specific inclusion: [shown in later section] The group owners / moderators may include custom text in each message footer.

Your Subscription: This is a link to your Subscription page for this group. See the Help page for more information on your Subscription Options.

Contact Group Owner: This is a mailto: link — it causes your email interface to open a new message composition window, directed to the group's +owner address. The message will be forwarded to each Owner and Moderator of this group (except that each individual owner/mod may opt out of receiving such messages). The new message will have the Subject line filled in, but will not contain a quote of the original (for that use Reply online). Note that proper functioning of this link is subject to the capabilities of your email interface and possibly to the settings in your operating system (default email client application).

Leave: This is a link to a page that will unsubscribe you from this group. The email address at the end of this line is your (the addressee's) subscription address. It is there to help with unsubscribe requests.

Unformatted (plain-text) Individual Message

You receive all messages sent to this group: This text reflects your Message Selection setting, under Advanced Preferences in your Subscription page. Muted threads or hashtags not included. The alternate text is "Every message in topics or hashtags you are following is emailed to you." and optionally
"The first message of every new thread is also emailed to you."

View/Reply Online: This is a link to the message, shown in the group's Messages section. The number that follows is the message number.

Mute This Topic: This is a link to a page which will Mute this topic so that you do not receive further messages (by email) in this topic. See the Help page for more information on Muting and Following topics.

Follow This Topic: [not shown] This is a link to a page which will Follow this topic so that you receive further messages (by email) in this topic. This will only be seen if you have selected Following Only and First Message Also in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Unfollow this topic: [not shown] This is a link to a page which will unfollow this topic so that you do not receive further messages (by email) in this topic. This will only be seen if you have selected Following Only in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Mute #hashtag: This is a link to a page which will Mute the named hashtag so that you do not receive further messages (by email) that have this hashtag. If there is more than one hashtag on this topic there will be a link for each. See the Help page for more information on Muting and Following hashtags.

Group-specific inclusion: [shown in later section] The group owners / moderators may include custom text in each message footer.

Group Owner: This is a mailto: link — it causes your email interface to open a new message composition window, directed to the group's +owner address. The message will be forwarded to each Owner and Moderator of this group (except that each individual owner/mod may opt out of receiving such messages). The new message will have the Subject line filled in, but will not contain a quote of the original (for that use Reply online). Note that proper functioning of this link is subject to the capabilities of your email interface and possibly to the settings in your operating system (default email client application).

Leave: This is a link to a page that will unsubscribe you from this group. The email address at the end of this line is your (the addressee's) subscription address. It is there to help with unsubscribe requests.

Formatted, aka Full Featured, Digest of Messages

Header at the top of the digest:

Logo: [upper left corner] This is a link to the Groups.io home page, if you are logged in this page shows a list of your group subscriptions and allows you to manage muted and followed topics and hashtags.

This is a digest for: The email address that follows is a link to your group's home page.

Change Your Subscription: This is a link to your Subscription page for this group. See the Help page for more information on your Subscription Options.

TOPICS IN THIS DIGEST: This is a list of the topics included in this digest. Each subject text is a link to that topic in the body of the digest. If there is a number present after the subject text it is the count of messages of that topic included in this digest.

Footer under each message:

View/Reply Online: This is a link to the message, shown in the group's Messages section, with the Reply composition box open. The number that follows is the message number.

Reply to Group: This is a mailto: link — it causes your email interface to open a new message composition window, directed to the group's posting address. The new message will have the Subject line filled in, but will not contain a quote of the original (for that use Reply online). Note that proper functioning of this link is subject to the capabilities of your email interface and possibly to the settings in your operating system (default email client application).

Reply to Sender: This is a mailto: link — it causes your email interface to open a new message composition window, directed to the sender's address. The new message will have the Subject line filled in, but will not contain a quote of the original (for that use Reply online). Note that proper functioning of this link is subject to the capabilities of your email interface and possibly to the settings in your operating system (default email client application).

Mute This Topic: This is a link to a page which will Mute this topic so that you do not receive further messages (by email) in this topic. See the Help page for more information on Muting and Following topics.

Follow This Topic: [not shown] This is a link to a page which will Follow this topic so that you receive further messages (by email) in this topic. This will only be seen if you have selected Following Only and First Message Also in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Unfollow this topic: [not shown] This is a link to a page which will unfollow this topic so that you do not receive further messages (by email) in this topic. This will only be seen if you have selected Following Only in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Top ^: This is a link back to the Topics list at the head of this digest.

New Topic: This is a link to the New Topic page in this group.

Footer at the bottom of the digest:

Logo: This is a link to the Groups.io home page, if you are logged in this page shows a list of your group subscriptions and allows you to manage muted and followed topics and hashtags.

... you are subscribed to: The email address that follows is a link to your group's home page.

unsubscribe here: This is a link to a page that will unsubscribe you from this group. 

Unformatted, aka Plain, Digest of Messages

Header at the top of the digest:

This is a digest for: The email address that follows the group's posting address. It may appear as a mailto: link if your email interface automatically linkifies email address syntax. The web address that follows is the group's home page address. It may appear as a link if your email interface automatically linkifies URL address syntax.

To unsubscribe, visit: The web address that follows is a page that will unsubscribe you from this group. It may appear as a link if your email interface automatically linkifies URL address syntax.

Topics in this digest: This is a list of the topics included in this digest. If there is a number present after the subject text it is the count of messages of that topic included in this digest.

Footer under each message:

View This Message: The web address that follows is the message, shown in the group's Messages section. It may appear as a link if your email interface automatically linkifies URL address syntax. The number at the end of the URL is the message number.

Reply To This Message: The web address that follows is the message, shown in the group's Messages section, with the Reply composition box open. It may appear as a link if your email interface automatically linkifies URL address syntax.

Mute This Topic: The web address that follows is a page which will Mute this topic so that you do not receive further messages (by email) in this topic. It may appear as a link if your email interface automatically linkifies URL address syntax. See the Help page for more information on Muting and Following topics.

Follow This Topic: [not shown] The web address that follows is a page which will Follow this topic so that you receive further messages (by email) in this topic.It may appear as a link if your email interface automatically linkifies URL address syntax. This will only be seen if you have selected Following Only and First Message Also in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Unfollow this topic: [not shown] The web address that follows is a page which will unfollow this topic so that you do not receive further messages (by email) in this topic. It may appear as a link if your email interface automatically linkifies URL address syntax. This will only be seen if you have selected Following Only in the Advanced Preferences section of your group Subscription. See the Help page for more information on Muting and Following hashtags.

Footer at the bottom of the digest:

Group Home: The web address that follows is the group's home page. It may appear as a link if your email interface automatically linkifies URL address syntax.

To change your subscription: The web address that follows is your Subscription page for this group. It may appear as a link if your email interface automatically linkifies URL address syntax. 

Terms of Service: The web address that follows the Groups.io's Terms of Service page. It may appear as a link if your email interface automatically linkifies URL address syntax.

Group-specific addition to the footer

In addition to the standard Groups.io footer, a group may insert its own custom text into the footer of outbound messages. This is done via the Message Formatting section of the group's Settings page. The Message Footer entry box is plain text (no formatting) but URL syntax will be recognized an linkified when included in formatted messages.

Because it adds to the bulk of every outbound message this facility should be used sparingly, if at all. For some types of groups a disclaimer or reference to the group guidelines may be appropriate.

Formatted footer, with group-specific addition:

The group-specific text is added between the message-related links and the subscription/group links, as shown above. In this example it is the text beginning with the word NOTE and ending with the link to the GroupManages Forum. Although only plain text is allowed in the added text, URL syntax will be recognized and linkified, as shown,

Plain text footer, with group-specific addition:

The group-specific text is added between the message-related links and the subscription/group links, as shown above. In plain text footers the small separators -=-=- are inserted automatically above and below the group-specific addition, if present.

FAQ

Can I reduce or eliminate the footer?

No.

Can my group's owner reduce or eliminate the footer?

No, but the group can add its own section to the footer, see above.