Automatic signature depending on Recipient e-mail address
Many companies would like to have separate signatures for internal and external e-mails.
Some companies might also want a specific signature for specific customers.
This is possible to implement with the OnRecipientsChanged event in Microsofts Mailbox 1.11 API for Web Add-Ins which was introduced at Ignite 2021 as mentioned here: What's new in Office Add-ins at Ignite 2021 - Microsoft 365 Developer Blog
I imagine a rule where an admin could define that is the To-field contains @contoso.com then one signature is applied, and to all other domains the default signature is applied.
CodeTwo is already using this in their e-mail Web Add-in, so implementing this in Xink would also help better compete.