When you switch to 'design tab' and press enter and go to the 'source tab' all `<br/>` are translated back to `<br>` and this seems to be invalid HTML and we are unable to save the Component.

It happens to all rich-text fields for all the Components. 

We migrated from 8.1 to 8.5 to 9.5. XSLT did not change, and it actually uses the default XSLT that came with the installation no there is not customization done.