Unable to install pem certificates

Fire TV Stick 4K

Version: FOS 8.1.5.5

I’ve tried following the guide ( Network Proxy (Developer Tools on Fire TV) | Amazon Fire TV )
but it fails after triggering the open intent I get a message similar to “unable to read file”

Has custom certs installation been removed?

Hello,
Thanks for posting. Could you please share the exact steps to reproduce the issue, the console logs, and a screenshot of the error message you received?