Hello Lera,
I am quite unsure what you meant by "clients" and so I would appreciate if you can provide more details about it. And while we are at that I wanted to clarify how the platform behaves by default during email responses.
When responding to an email interaction the editor does not append any of the previous messages in the thread. There is an option to preserve the entire thread by clicking on the Show Message History button as you have mentioned. If you choose Forward instead of Reply or Reply All however, the entirety of the thread is indeed preserved on the editor.
Curious to know why it seems like your editor is behaving differently. Are you perhaps using a 3rd party add-on or tool?
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Nico Feliciano
Genesys - Employees
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