Web UI requires internet — binary proxies all assets to CDN instead of serving locally

[BYK]

Description

The compiled OpenCode binary proxies all web UI asset requests to app.opencode.ai. Running opencode serve in an environment without internet access (air-gapped, corporate proxy, airplane) results in a blank page because the HTML, JS, CSS, and fonts cannot be fetched from the CDN.

The web UI assets are known at build time and can be embedded directly into the binary using Bun's compile-time asset embedding ({ type: "file" } imports). This would allow the server to serve them locally with a CDN fallback only for optional fonts.

Steps to reproduce

1. Build and run opencode serve on a machine without internet access
2. Open the web UI in a browser
3. Observe blank page — all asset requests fail because they proxy to app.opencode.ai

OpenCode version

1.2.26

OS

macOS, Linux, Windows

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• 【intranet 】Unable to connect. Is the computer able to access the URL? #12083: Also reports opencode serve web UI failing in environments without internet/external network access (intranet/air-gapped)

If your issue is distinct (e.g. you are specifically requesting asset embedding rather than reporting a connection error), please clarify the difference so we can keep both open if warranted.

[BYK]

Thanks for flagging — #12083 is about connecting to LLM API providers from an intranet environment (the Unable to connect error when hitting model endpoints). This issue is specifically about the web UI assets (HTML, JS, CSS, fonts) being proxied from app.opencode.ai instead of served from the binary, which means opencode serve shows a blank page without internet even if the LLM provider is reachable on the local network. Different root cause, different fix.

[thdxr]

Fixed by #19299 - The WebUI is now embedded directly in the binary using Bun's compile-time asset embedding. Assets are served locally instead of proxying to CDN, enabling offline/air-gapped usage.

[thdxr]

Closing as fixed by #19299