Automatically fallback clipboard setting from external to terminal when used through SSH

Description of the problem or steps to reproduce

When used locally, clipboard setting must be set to external to be able to copy text outside of micro editor with use of xclip and xsel.

When starting micro through ssh with clipboard set to external an error is displayed. The error is not present when clipboard is set to internal.

But when using micro locally with clipboard set to internal copying text outside of micro editor doesn’t work.

This is a problem when using micro alternatively locally and through ssh.

Specifications

Micro: Version: 2.0.8
Commit hash: cfcb2e45
Compiled on October 06, 2020
OS: Ubuntu 20.04
Terminal: xterm-256color (gnome terminal)

Fix suggestion

clipboard setting should be external. When micro starts and setting is external, check presence of SSH environment variables (e.g. SSH_CONNECTION) to determine if run through ssh. In this case silently and automatically fallback to internal.

Reproduce the reported behavior by using the clipboard setting as external locally and through SSH, then inspect the startup path that reads this setting and the SSH environment. Done means external clipboard use remains available locally, while an SSH session silently uses the internal clipboard without an error.