[Bug] Desktop v1.18.5: UnsupportedContentType error on project reload after update

[Start-Gao]

Description

After upgrading to Desktop v1.18.5, the app shows a notification on startup:

无法重新加载test
UnsupportedContentType

The "test" project is the current workspace directory.

Root Cause

The error UnsupportedContentType originates from the generated client SDK (packages/client/src/generated/client.ts), thrown when the server returns a Content-Type header that is neither application/json nor text/event-stream.

This appears to be related to the dual-server compatibility ("Current" architecture) changes in #38462. The new server protocol detection logic is likely sending a request that gets back an unexpected Content-Type response.

Environment

• OpenCode Desktop v1.18.5
• Windows 11
• Project: D:\Workspace\Demo\test

Steps to Reproduce

1. Install/upgrade to Desktop v1.18.5
2. Open the app
3. The app loads the "test" project and shows the error notification

Workaround

(Needs confirmation)

Screenshots

N/A (terminal error notification)

Additional Context

• Clearing Desktop cache did not resolve the issue
• The project directory contains normal files (json, html, mjs, md)

[Start-Gao]

[chenye041208]

Can reproduce this on Windows 10 with v1.18.5.

Steps I confirmed:

1. Reset OpenCode (delete AppData/Roaming/ai.opencode.desktop)
2. Re-open the app — no error at this point
3. Add any folder as a project (even an empty folder)
4. Close and re-open the app
5. UnsupportedContentType error pops up every time

So this is not project-specific — any workspace triggers it.

Screenshot attached.

[SherUnlocked-4869]

I also encountered the same issue

[wujialeHK]

I also encountered this problem. In addition, I closed the old session and the session creation failed when I reopened the new session. Do you have this problem?

[pppbfw]

Me too, the desktop is terrible.

[zhangxyjlu]

I also encountered the same issue

[satrapu]

I can reproduce this consistently on a clean Windows machine with a local Ollama setup.

Environment

• OS: Windows 11 Pro x64
• OpenCode Desktop: 1.18.5 (installed via winget)
• Ollama: 0.32.3
• GPU: NVIDIA GeForce RTX 5080 (16 GB VRAM)
• CPU: Intel Core Ultra 7 265F
• RAM: 32 GB DDR5

Ollama configuration

OpenCode is configured to use the local OpenAI-compatible endpoint:

{
  "$schema": "https://opencode.ai/config.json",
  "enabled_providers": ["ollama"],
  "provider": {
    "ollama": {
      "options": {
        "baseURL": "http://localhost:11434/v1"
      },
      "models": {
        "qwen3-coder:30b": {},
        "devstral:24b": {}
      }
    }
  }
}

Models

• qwen3-coder:30b
• devstral:24b
• qwen2.5-coder:14b

Reproduction

The issue occurs regardless of the opened workspace:

• empty folder
• Git repository (~414 MB, ~4,300 files)

Steps:

1. Launch OpenCode Desktop.
2. Open any folder (empty or existing repository).
3. Select an Ollama model.
4. Ask a simple question (even "Hello").

Expected

The prompt should immediately be sent to Ollama and inference should start.

Actual

OpenCode stays on Thinking for several minutes (or indefinitely).

During this time:

• ollama ps shows no running model
• GPU usage stays essentially idle
• No request appears to reach Ollama

Running the exact same prompt directly works immediately:

ollama run qwen3-coder:30b

Additional diagnostics

The local OpenAI-compatible endpoint is working correctly:

Invoke-WebRequest http://localhost:11434/v1/models

returns:

• HTTP 200
• Content-Type: application/json
• valid model list

The problem also reproduces when launching OpenCode via:

ollama launch opencode

so it does not appear to be caused by my manual configuration.

The issue is also reproducible:

• with an empty workspace
• in Airplane Mode (no Internet connection)

Logs

renderer.log consistently contains:

Failed to finish bootstrap instance ClientError: UnsupportedContentType

This appears during application startup, before any prompt is sent to Ollama.

The most important observation is that while OpenCode displays Thinking, ollama ps remains empty, suggesting that the request is never sent to Ollama.

[Nicol1B13]

I can confirm this regression on Windows 11 with OpenCode Desktop 1.18.5 (v1.18.4 works fine).

Note: The CLI (terminal) version works without issues. The "Unsupported ContentType" error only pops up in the Desktop GUI on the very 1st session initialization (cold start). Subsequent sessions load normally.

[walunt236]

太恼火了干净安装进去弹的第一个弹窗就是无法重新加载项目