Update: Tested multiple version combinations

After extensive testing, I found an interesting pattern:

✅ Working (2023):

• code-server v4.20.0 + Copilot v1.149.652 + Copilot Chat v0.11.1
• No errors, works perfectly
• BUT: No agent mode (agent mode was released in Feb 2025)

❌ Not Working (2025+):

• code-server v4.99.3 + Copilot Chat v0.26.2025040204 (April 2025)
• code-server v4.111.0 + Copilot Chat v0.39.2026030507 (March 2026)
• Both show same errors: API proposals not found, "No default agent registered"

Question for the community:

Is there a fundamental incompatibility between code-server and Copilot versions with agent mode (Feb
2025+)?

It appears that all Copilot versions released after agent mode require VS Code APIs that code-server
doesn't support. Can anyone confirm if they've successfully run Copilot with agent mode on code-server?

If this is a known limitation, what's the recommended approach:

1. Wait for code-server to implement the missing APIs?
2. Stick with pre-2025 Copilot versions (no agent mode)?
3. Use alternative solutions (official VS Code Server, Codespaces, etc.)?

Thanks for any insights!

Partially Working - Seeking Better Version Combination

I found this combination partially works on code-server v4.102.0-rc.1:

code-server: v4.102.0-rc.1
GitHub Copilot: 1.343.1676
GitHub Copilot Chat: 0.29.0

What works: Chat responses, agent mode (editAgent), code generation

Issues:

• UI login button doesn't work properly
• Some authentication flow issues

Questions

1. Is there a more stable/newer version combination that works better on code-server? I'd like to use a more recent version if
possible while maintaining stability.
2. About the navigator is now a global in nodejs error:
- Why does this error occur?
- I see it appears in Node.js v22 (bundled with code-server v4.102+)
- v0.29.0 tolerates it (non-fatal), but v0.38+ crashes from it
- Is there a way to completely fix this error, rather than just tolerating it?
3. Root cause understanding:
- Is this a Node.js v21+ breaking change?
- Is it a code-server-specific issue, or does it affect VS Code OSS in general?
- Are there plans to fix this in either code-server or Copilot extension?

Any insights would be appreciated. Thanks!

I ran into this same thing last year - code-server's VS Code version drift kills Copilot compatibility. The navigator global error and missing API proposals are red flags that the VS Code version gap is too big. v4.111.0 is ancient compared to what Copilot Chat expects now.

Your best bet: downgrade code-server to v4.20.x. That's the last version where Copilot Chat v0.11.1 worked reliably before agent mode existed. If you need agent mode, you're stuck waiting for code-server to catch up - v4.112+ is supposed to close the gap but no ETA.

Alternatively, try code-server v4.109.2 with Copilot Chat v0.37.20260130 - that combo was stable for me when I needed older features. The navigator fix won't help here; it's a deeper API mismatch.