To ensure that all emails remain in the same thread, you can simply leave the subject line of each subsequent email blank. By doing so, the new emails in your sequence will be grouped with the original (first-step) message, forming a coherent thread.
Please note. If the subject line of the first email in a thread contains symbols or commonly used prefixes such as "Re:" or similar, the follow-up emails will not be grouped in the same thread and they will not have a subject line.
How to check how your emails will look like
There is no way to test it immediately, except for adding your email address to the sequence. However, you can send a test email to your email address to see what the email template will look like when it is sent to recipients.
To send a test email, simply open an email, click the downward arrow next to the 'Save' button, and select 'Send test email' from the dropdown menu. It's important to note that each template will be sent individually, and they won't be linked in a sequence.
