Ok, this is weird. I added your suggested code and saved it. Nothing changed on the website but when I went back to swift page builder I could see a field to enter your email address and a send button. Besides that I also need fields for first name, name and company the code also changed to
<input id="mce-EMAIL" class="required email" title="Enter your email address" autocomplete="off" name="EMAIL" type="email" value="" placeholder="Enter your email address" />
<div id="mce-responses" style="display: none;"></div>
<!-- real people should not fill this in and expect good things - do not remove this or risk form bot signups-->
<div style="position: absolute; left: -5000px;"><input tabindex="-1" name="b_a3950048c69f7be72a27013a9_68a002176a" type="text" value="" /></div>
<input id="mc-embedded-subscribe" name="subscribe" type="submit" value="SUBSCRIBE" />
I wasn’t sure what my “action URL” was. Is //next-organic.us11.list-manage.com/subscribe/post?u=8a37db3fdac5e9bdd3f1550a4&id=ddbfb2f414 correct?
Why isn’t it possible to save the mailchimp code in the swift page builder? It worked once but never again.
Thanks for you help.