OpenCode Desktop v1.17.11 — Renderer freezes on streaming responses (ResizeObserver loop) #34038

Description

Environment:

OpenCode Desktop v1.17.11 (auto-updated from 1.16.2)
OS: Windows (x64)
GPU-accelerated renderer (Electron/Chromium)
Steps to reproduce:

Start a new chat with an agent that uses tool calls (e.g. MCP servers)
Send a query
Observe: during or after streaming the response, UI freezes for 1-6 seconds
Logs (from %APPDATA%\ai.opencode.desktop\logs):

renderer.log shows bursts of hundreds of:

[error] ResizeObserver loop completed with undelivered notifications.
Example burst — 36 errors in 5 seconds (11:21:43–11:21:48):

[11:21:43.729] [error] ResizeObserver loop completed...
[11:21:43.878] [error] ...
[11:21:48.987] [error] ...
window.log also shows renderer process killed on previous v1.16.2:

[error] (window) app render process gone { reason: 'killed', exitCode: -1073741510 }
main.log shows clean startup with all servers ready — confirming the issue is in the renderer, not in the backend or providers.

What was ruled out:

API provider disconnections (no [global-sdk] event stream error)
MCP server counts (reduced from 7 to 4, no improvement)
Plugin interference (notificator removed)
"type": "module" in package.json (added)
Root cause (deduced): When the model streams a response containing large tool call results (MCP results, file patches, etc.), the chat DOM tree grows rapidly. Electron's ResizeObserver fails to deliver observations within the animation frame budget, causing cascading re-layouts and blocking the renderer process for seconds.

Expected behavior: UI should remain responsive during and after streaming.

Workaround found: Clearing chat history and starting a fresh chat helps temporarily, but the problem returns as history accumulates.

Plugins

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OpenCode version

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Steps to reproduce

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Screenshot and/or share link

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Operating System

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Terminal

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