Changing your account password in Thunderbird is a simple process that helps enhance your email security. Follow these steps to update your password:

1. Open Thunderbird and go to 'Tools'.
2. Click on 'Options' and select 'Account Settings'.
3. Choose the account for which you want to change the password.
4. Click on 'Server Settings' under the account.
5. Find the 'Password' field and delete the existing password.
6. Enter your new password and click 'OK'.

After following these steps, your account password in Thunderbird will be successfully updated, providing you with improved security for your emails.