I found a case that shouldn't happen on Freshdesk when inserting an HTML email signature. For example, if you have a rich email signature, with tables (usually HTML signatures are created with HTML tables)
Freshdesk adds an external-border in the settings. Apparently, this is because of the Redactor editor ( WYSIWYG html editor create by imperavi). This is not meant to happen. Freshdesk has an error in this part because of the Redactor editor.
See image example, with an email sigature HTML created with the Bybrand.
The email signature created with Bybrand does not have a border, and when pasting on Freshdesk the border is displayed.