@Jonathon Aroutsidis
Thank you for your product feedback!
When it comes to using Let's Encrypt, I found some documentation which walks through how to integrate Let's Encrypt with the Azure Key Vault. When it comes to your product feedback, I've passed this along to our Key Vault team and would highly suggest leveraging our new User Voice forum to share this feature request, so our engineering team can take a look at implementing this.
Azure Key Vault Let's Encrypt
Azure Key Vault Certificates with Let's Encrypt as the Issuer CA - 3rd Party Link
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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