[BUG] Claude Desktop App — Screen Flickering & Mouse Lag on Windows

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?

Bug Report: Claude Desktop App — Screen Flickering & Mouse Lag on Windows

Summary

Claude Desktop application causes screen flickering and mouse input lag (stuttering) when moving the cursor over the application window on Windows. The issue is related to Electron GPU compositing and DWM interaction, particularly on multi-GPU desktop systems.

Environment

• OS: Windows 11 (fresh install, latest updates)
• CPU: AMD Ryzen 9 9950X 16-Core (with integrated AMD Radeon Graphics)
• dGPU: NVIDIA GeForce RTX 5070 Ti (Driver 596.36, CUDA 13.2)
• iGPU: AMD Radeon Graphics (Ryzen integrated)
• RAM: 128 GB
• Monitor: Dell S2716DG, 2560x1440 @ 144Hz, connected via DisplayPort to RTX 5070 Ti
• Motherboard: MSI MS-7E49 (X870E)
• Claude Desktop Version: 1.6259.1.0 (Microsoft Store)

Steps to Reproduce

1. Install Claude Desktop from Microsoft Store on a system with dual GPUs (integrated + discrete)
2. Launch Claude Desktop
3. Move the mouse cursor over the Claude application window
4. Observe: screen flickering and mouse cursor stuttering/lag

Expected Behavior

Smooth cursor movement and no screen flickering when interacting with the application window.

Actual Behavior

• Rapid screen flickering when hovering/moving mouse over the Claude window
• Mouse cursor stutters and lags during movement over the application
• GPU utilization spikes to 15-20% on NVIDIA GPU just from mouse movement over the window
• DWM (Desktop Window Manager) utilization reaches 34% on the GPU during window interaction

Root Cause Analysis

The issue stems from Electron's GPU compositing layer interacting with Windows DWM on multi-GPU desktop systems:

1. DWM binds to the GPU owning the display output. On desktops with the monitor connected to the discrete GPU (NVIDIA), DWM must composite all windows on that GPU.

1. Electron GPU compositing causes excessive redraws. When the mouse moves over the Claude window, the Electron renderer triggers continuous frame repaints. DWM then re-composites these frames on the NVIDIA GPU, creating a bottleneck.

1. Cross-GPU frame transfer (if iGPU is used for rendering). When Claude is set to render on the integrated AMD GPU while DWM runs on NVIDIA, frames must be copied between GPUs, adding latency and causing visible stuttering.

1. The issue does NOT occur on Linux (Ubuntu), where the Wayland/X11 compositor handles GPU offload rendering natively via PRIME/DMA-BUF without forcing all UI processes onto the discrete GPU.

Workaround Found

Launching Claude Desktop with the --disable-gpu-compositing flag resolves both the flickering and mouse lag:

"C:\Program Files\WindowsApps\Claude_1.6259.1.0_x64__pzs8sxrjxfjjc\app\Claude.exe" --disable-gpu-compositing

This forces Claude to use software compositing (CPU-based), which eliminates the DWM/GPU compositing conflict. With a modern CPU (Ryzen 9 9950X), there is no noticeable performance impact for a text-based application.

Suggested Fix

1. Add a "Disable Hardware Acceleration" toggle in Claude Desktop Settings (like Chrome, VS Code, Discord, and other Electron apps provide).

1. Auto-detect multi-GPU configurations and default to software compositing or use --disable-gpu-compositing automatically on desktop systems with multiple GPUs.

1. Alternatively, pass --disable-gpu-compositing by default on Windows for the Claude Desktop app, since it is primarily a text-based interface and does not benefit from GPU compositing.

Additional Notes

• Claude Desktop spawns 12 processes consuming ~2 GB of RAM total
• The --disable-gpu flag also resolves the issue but is more aggressive than necessary
• Setting GpuPreference=1 (Power Saving / iGPU) or GpuPreference=2 (High Performance / dGPU) in Windows Graphics Settings does not resolve the issue — only disabling GPU compositing helps
• The BIOS "Hybrid GPU" option on the MSI motherboard does not change DWM behavior on Windows (unlike NVIDIA Optimus on laptops)

Reporter

• Date: 2026-05-07
• System: Desktop workstation (MSI X870E / Ryzen 9 9950X / RTX 5070 Ti)

What Should Happen?

The Claude Desktop application should render its window smoothly without screen flickering or mouse cursor lag when moving the mouse over the application window. On a system with dual GPUs (integrated AMD Radeon + discrete NVIDIA RTX 5070 Ti), the app should either:

1. Provide a "Disable Hardware Acceleration" toggle in Settings (like Chrome, VS Code, Discord do)
2. Auto-detect multi-GPU desktop configurations and default to software compositing
3. Or pass --disable-gpu-compositing by default, since Claude is a text-based app and does not benefit from GPU compositing

Currently the only workaround is launching with --disable-gpu-compositing flag manually via a custom shortcut.

Error Messages/Logs

Steps to Reproduce

1. Install Claude Desktop from Microsoft Store on a Windows 11 system with dual GPUs (integrated AMD Radeon iGPU + discrete NVIDIA GPU), monitor connected to the discrete GPU
2. Launch Claude Desktop normally (without any custom flags)
3. Move the mouse cursor over the Claude application window
4. Observe: screen flickering and mouse cursor stuttering/lag
5. Additionally, open Task Manager → Performance → GPU: notice NVIDIA GPU utilization spikes to 15-20% just from mouse movement over the window, DWM reaches up to 34%

Workaround: launching Claude with --disable-gpu-compositing flag eliminates the issue completely.

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

N/A (this is a Claude Desktop issue, not Claude Code) Claude Desktop Version: 1.6259.1.0 (Microsoft Store)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

_No response_