The Mailman subscription widget allows site visitors to add themselves to a mailing list using the Mailman subscription service. Besides the title, the Mailman subscription Block is not visually customizable.
Add a Mailman subscription widget
From the administration bar, select Workbench, and then select My Dashboard.
Select a content page from the Content list or create a new page from Content types.
On the content page, select the Layout tab.
Select + Add section if applicable, then select + Add block.
Under Content, select Mailman subscription.
Enter a Title. The Title will appear as a Block header unless Display title is unselected.
From the Mailman server drop-down menu select your desired server.
Under Mailman mailing list subscription URL, type the name of your mailing list.
Select Add block.
Select state from the Change to: drop-down menu.
Select Save layout.
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