desktop: attachment button fails with request failed (desktop IPC handler failed) #50309

Description

Summary

Clicking the attachment button in OpenCode Desktop fails immediately with request failed (desktop IPC handler failed). File dialog never opens, so no file can be attached at all.

Environment

• opencode version: 2.0.11 (desktop, user-reported; opencode --version Unavailable: CLI not in PATH)
• OS: Microsoft Windows [Version 10.0.26200.9445] (Windows_NT 10.0.26200 win32 x64)
• Terminal: xterm-256color ($TERM=xterm-256color, desktop app, $TERM_PROGRAM empty)
• Shell: C:\WINDOWS\system32\cmd.exe
• Install/channel: latest (runtime snapshot)
• Active plugins: none found (no ~/.config/opencode/opencode.json, no project opencode.json, no .opencode/plugin)

Reproduction

1. Fresh install OpenCode Desktop 2.0.11 on Windows
2. Open session in C:\Users\Sakinah\Documents\Default Project (empty folder, non-git)
3. Click attachment button in composer
4. Immediate notification request failed (desktop IPC handler failed), picker never opens

Expected Behavior

File picker dialog opens so a file can be selected and attached.

Actual Behavior

Error notification appears instantly, no dialog, attachment impossible. Affects all files.

Additional Context

• Frequency: consistent (100%), fresh install, first use
• Tried Run as administrator, still fails
• Server log (~/.local/share/opencode/log/opencode.log, 32KB) shows only routine INFO/WARN (provider.updated, model.updated, worktree discovery failed for non-git dir), no upload ERROR — points to desktop client IPC, not server
• opencode and gh CLIs not in PATH, could not auto-publish
• Workaround: manual copy via Explorer into project dir works for reading files

Plugins

No response

OpenCode version

No response

Steps to reproduce

No response

Screenshot and/or share link

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Operating System

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Terminal

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