Copy and paste is broken (Windows Putty SSH to Linux Mint)

[WelliSolutions]

Describe the bug

I can no longer copy text from Copilot simply selecting text with the mouse.
I can no longer paste text to Copilot using right click.

This majorly breaks my workflow. How do I get my prompts from Windows to Linux now, and the results back?

Affected version

GitHub Copilot CLI 1.0.9.

Steps to reproduce the behavior

1. Run Putty on Windows, connect to the Linux machine running Copilot
2. Start CoPilot
3. Copy a prompt on the Windows machine
4. In Putty, right click to insert the prompt
5. Note: nothing happens, the prompt is not inserted
6. Enter /feedback manually and choose option 2, submit a bug report
7. Copilot cannot open a browser (that's expected)
8. Mark the URL in Putty with the mouse
9. Paste the URL (in Notepad or wherever)
10. Note: the clipboard does not contain the URL, it wasn't copied

Expected behavior

1. Right click in Putty pastes the clipboard into Copilot
2. Selecting text with the mouse copies the selected text to the clipboard

This worked in previous versions of Copilot (probably 1.0.7 or 1.0.8)
This works in Claude Code 2.1.78 and Codex 0.115.0, so it really is a shortcoming of Copilot.

Additional context

OS running Putty: Windows 10 x64 with Putty
OS running Copilot: Linux Mint
Shell: bash

I have verified that copy/paste works in the same Putty session on other programs, e.g. nano or simply the Bash itself.

[ldarby-hpe]

Probably the same issue exists on Debian 13 with X11 and running copilot in an xterm, but I confirmed it started in 1.0.8. The change log in 1.0.8 has this:

Alternate screen buffer is now enabled by default for a cleaner terminal experience

and I found that can be turned off with copilot --no-alt-screen, and that worked around the issue, i.e. highlight to copy works again - does it fix it in Putty too?

[devm33]

Hi @WelliSolutions and @ldarby-hpe, we are rolling out the alternate screen buffer rendering to fully fix flickering and flashing, as well as enabling better UI rendering generally. However, it does mean some trade-offs around interaction.

If you want native mouse interactive without disabling the alt screen rendering, you can run with --no-mouse (which will persist "mouse": false into your .copilot/config.json) Note, that will disable mouse scrolling though, you will need to use page-up and page-down keys.

[ldarby-hpe]

@devm33 Thanks, --no-mouse works for me. I was not aware that anything in a terminal could disable highlight to copy in this way. I knew that alsamixer supported volume control with the mousewheel, and have now just realised it also disables highlight to copy as well. It's called terminal mouse-reporting mode, and unfortunately it doesn't look like it's possible to capture the wheel only (buttons 4 and 5) but not capture buttons 1 2 and 3 for copy/paste (it would be possible but as a new feature that all terminals would need to implement, according to copilot).

With the new alt-screen, and with mouse support enabled, shift-click works too though, if people prefer that and having the scroll wheel, I'm not sure what I'll choose yet though.