What's happening?
Users experience behaviors with emails in Dynamics 365 Customer Service, where images pasted into the Rich Text Editor (RTE) are not displayed properly for the email recipient.
Reason:
Users do not have privileges to to view the content.
Resolution:
Set the property "disableDefaultImageProcessing" to "true" within the configuration of the RTE control.
See the Add the rich text editor control to a model-driven app - Power Apps | Microsoft Learn for more information.