bug: Native support for fish shell in Copilot Chat: Multiline command handling and terminal stability

Non-support of Fish Shell in GitHub Copilot Chat: Multiline Command Issues & Terminal Crashes

Problem Summary

Copilot Chat in VS Code does not natively support fish shell. This lack of support leads to significant friction when working with multiline shell commands, particularly for workflows commonly used with git or node and other tools that require structured multiline input.

For example, the intended way to commit with a multiline message would be:

git commit -m "
feat: Lorem Ipsum

- Lorem Ipsum
- Lorem Ipsum
"

But inside Copilot Chat (with fish), this must be rewritten as:

git commit -m "feat: Lorem Ipsum" -m "" -m "- Lorem Ipsum" -m "- Lorem Ipsum"

This workaround is unintuitive and easy to get wrong, especially for users who expect standard Unix multiline syntax. Defining expected terminal behavior in copilot-instructions.md or other config does not reliably resolve this issue.

Additional Issues

• Sometimes the Copilot terminal process crashes when attempting such workarounds, resulting in lost connection between the chat and the integrated terminal.
• Native fish shell features (composition, history, etc.) do not function as expected.

Request

• Is there a plan to natively support fish shell in Copilot chat to improve seamless multiline command handling and stability?
• Would supporting more shells (like fish) reduce errors and make cross-shell workflow more robust?

References (Related Issues and Discussions)

• Org Discussion: Non-support of Fish Shell in Copilot
• VS Code #284395: Integrated terminal default shell issues
• Similar problem: Google notation/multiline docstrings