The message archive shows all messages sent via your group. You can search the entire message archive with the search bar at the top of the page.
Messages are shown in a threaded view by default whereby all messages in the same conversation are grouped together. This can be switched off by clicking the Settings icon above the message list and toggling the “Conversation view on/off” option.
Also, by default, the messages are shown in a split panel view with a list of messages and a panel showing the selected message. This can be toggled by clicking the list button next to the settings button.
When viewing a message, administrators have the option to; delete the message, resend the message, or switch to viewing the clean or raw version of a message.
The clean version of a message is shown by default and strips off all and previous replies that build up at the bottom of long email chains. The raw version is the entire message exactly how it was sent to the group.
If you don't want a message archive for your group, it can be completely disabled from your group Settings.
Messages are stored in the archive indefinitly. You can scroll down to see the most recent 1,000 and use the serach function to see older messages.
For groups on the free plan only the last three months worth of messages are stored.