[BUG] Confirming same issue — macOS 26.5.1 (build 25F80), Apple Silicon (arm64), Claude Desktop 1.14271.0

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Confirming same issue — macOS 26.5.1 (build 25F80), Apple Silicon (arm64), Claude Desktop 1.14271.0
Reproducing the V8 renderer OOM crash on launch. Main process starts fine (logs "The running client is already the latest version"), but the renderer crashes within seconds with SIGTRAP and the window never appears.
Environment:

macOS: 26.5.1 (build 25F80)
Hardware: Apple Silicon (arm64), MacBook Pro
Claude Desktop: 1.14271.0

Confirmed crash signature (via --enable-logging=stderr):
ERROR:electron/shell/common/node_bindings.cc:189] OOM error in V8: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory
zsh: trace trap /Applications/Claude.app/Contents/MacOS/Claude
Repeats 4x then trace-traps. RSS is low at crash time, so this is V8 old-space exhaustion in the isolate, not system memory pressure.
Tried, did not fix: full clean reinstall; cleared ~/Library/Application Support/Claude + Caches + Logs; removed window-state.json, vm_bundles, local-agent-mode-sessions. Disabling all MCP connectors via config did not help. --disable-gpu alone fails to render. --js-flags="--max-old-space-size=8192" did not help either — the OOM is not avoidable via external flags.
App is fully unusable on this machine. Using claude.ai in browser and Claude Code CLI as workarounds.

What Should Happen?

The desktop app should launch normally and the main window should render, showing the chat interface — the same way it did before, and the way it still works for accounts on earlier macOS versions.

Error Messages/Logs

Crash captured via: /Applications/Claude.app/Contents/MacOS/Claude --enable-logging=stderr

[ERROR:electron/shell/common/node_bindings.cc:189] OOM error in V8: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory
[ERROR:electron/shell/common/node_bindings.cc:189] OOM error in V8: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory
[ERROR:electron/shell/common/node_bindings.cc:189] OOM error in V8: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory
[ERROR:electron/shell/common/node_bindings.cc:189] OOM error in V8: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory
zsh: trace trap  /Applications/Claude.app/Contents/MacOS/Claude --enable-logging=stderr

Note: RSS at crash time is low, so this is V8 old-space exhaustion in the isolate, not system memory pressure. Crash is the same on every launch (100% reproducible).

Steps to Reproduce

Use a Mac on macOS 26.5.1 (build 25F80), Apple Silicon (arm64).
Install Claude Desktop 1.14271.0 (downloaded fresh from claude.ai/download).
Launch the app.
The main process starts and logs "The running client is already the latest version", but the renderer crashes within ~seconds with a V8 JavaScript heap out-of-memory error (SIGTRAP) and no window ever appears.
Crash is 100% reproducible on every launch.

Confirmed crash log (via --enable-logging=stderr):

OOM error in V8: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory → repeats 4x → trace trap.
Already tried, none worked: clean reinstall; cleared all caches/logs; removed window-state.json, vm_bundles, local-agent-mode-sessions; disabled all MCP connectors via config; --disable-gpu; --js-flags="--max-old-space-size=8192". The OOM is not avoidable from outside the app.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.51 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_