Issue: 

When the Checkout Custom Field extension is installed the Invoice and Shipment emails that go out are missing much of the information that is supposed to show up in them. When this extension is removed the emails display correctly  

The reason is that Magento added many new fields to the email template and they're not setup in the app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender files properly.

Solution:

The issue is from our module's bug when the current version 1.2.6 is not compatible well with M2.4.4 at this time.
To solve it, we have edited these files:
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/CreditmemoCommentSender.php
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/CreditmemoSender.php
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/InvoiceCommentSender.php
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/InvoiceSender.php
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/OrderCommentSender.php
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/ShipmentCommentSender.php
app/code/Bss/CheckoutCustomField/Model/Plugin/Sales/Order/Email/Sender/ShipmentSender.php


Please overwrite these files on the site to fix the issue.


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