Yes, Benjamin, it is technically possible to send emails to A and B such that each recipient believes the email was sent to both, but in reality, they receive different content. This is commonly done using the BCC (Blind Carbon Copy) field or by sending separate, customized emails to each recipient.

How it works:

• BCC Method: You send a single email with A in the "To" field and B in the "BCC" field (or vice versa). Each recipient sees only their own address in the "To" field, but the content is the same for both. However, this doesn’t allow for different content.

• Separate Emails: You send two separate emails, each addressed to A and B in the "To" field, but with different content. Most email clients allow you to customize the body for each recipient, even if the "To" field appears identical. This is often used in email marketing or personalized communication.

• Email Merge Tools: Tools like Mail Merge (in Outlook, Gmail, or third-party services) allow you to send personalized emails to multiple recipients, making it appear as if everyone received the same email, when in fact the content is tailored.

Ethical Considerations:

• Transparency: It’s important to consider whether this practice is transparent and ethical, especially if the recipients expect the same information.
• Privacy: Ensure you’re not misleading recipients or violating privacy norms.

Would you like guidance on how to set this up in a specific email client or tool?

In Mozilla Thunderbird, you can send personalized emails to multiple recipients so that each recipient sees their own version of the email, while the "To" field appears to include everyone. Here’s how to do it:

Method 1: Manual Customization (Small Number of Recipients)

1. Compose a New Email: Open Thunderbird and click Write to start a new message.

2. Add Recipients: In the "To" field, add both A and B (e.g., a@example.com, b@example.com).

3. Customize Content for Each Recipient:

   • Write the email content for A.
   • Send the email to A.
   • Repeat the process for B, changing the content as needed.

   Note: This method requires sending two separate emails.

Method 2: Using Mail Merge (For Many Recipients)

Thunderbird doesn’t have a built-in mail merge feature, but you can use an add-on like Mail Merge to automate the process:

1. Install the Mail Merge Add-on:

   • Go to Tools > Add-ons and Themes.
   • Search for "Mail Merge" and install it.

2. Prepare Your Data:

   • Create a CSV file with columns for recipient emails and any custom fields (e.g., Name, CustomMessage).

3. Compose the Template:

   • Write your email in Thunderbird, using placeholders (e.g., {{Name}}, {{CustomMessage}}) for personalized content.

4. Run the Mail Merge:

   • Open the Mail Merge add-on.
   • Select your CSV file and template.
   • Send the emails. Each recipient will receive a personalized version, with the "To" field showing all recipients.

Method 3: BCC with Custom Content (Limited)

If you want to hide recipients from each other but still send different content:

1. Compose a New Email.

2. Add A to the "To" field and B to the "BCC" field.

3. Send the email to A with their content.

4. Repeat for B, swapping the "To" and "BCC" fields.

   Note: This method doesn’t truly show both recipients in the "To" field for each email.

Key Points:

• Thunderbird does not natively support sending different content to multiple recipients in a single email.
• For true personalization, use Method 1 (manual) or Method 2 (add-on).
• Always ensure compliance with privacy and ethical standards.

Would you like step-by-step screenshots or further clarification for any of these methods?