Feature Request: Per-Tab Option to Disable GPU Acceleration / Use Software Compositing

[T3hReaper]

Component:
Core :: Graphics: WebRender

Users often run GPU-intensive applications such as video games, graphics software, streaming tools, or 3D rendering suites alongside their browser. Currently, if a Firefox tab uses GPU features—like video decoding or WebGL—it can interfere with or compete for limited GPU resources, leading to lag, instability, or outright crashes in those other workloads.

A per-tab or per-site toggle to disable GPU acceleration would offer much-needed control in these scenarios.

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Description:

Use Case:

Suppose a user is gaming, rendering a video in DaVinci Resolve, running Blender, or livestreaming with OBS. These applications demand significant GPU bandwidth. Opening a Firefox tab that includes WebGL content, animated media, or auto-playing video can unexpectedly consume GPU resources, impacting performance across the board. While its possible to toggle Hardware Acceleration off completely in Firefox, this may cause unexpected rendering issues on websites, or degraded performance, until a full browser restart is initiated. 

There’s currently no way to tell Firefox:

• "Don’t use the GPU for this tab."

• Or "This tab doesn’t need acceleration—just render it quietly in software."

This results in unnecessary contention for GPU memory and cycles—especially for users on:

• Laptops with integrated graphics,

• Desktops with modest VRAM (<8GB),

• Workflows requiring tight GPU scheduling or real-time rendering.

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Proposed Feature:

Introduce a per-tab or per-site toggle to disable GPU acceleration and fall back to software rendering.

Implementation ideas:

• Right-click context menu on tabs: “Disable GPU acceleration for this tab”

• A toggle in about:performance or about:preferences

• A tab property viewable in Task Manager or devtools

• Possibly a site permission (like location or camera access)

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Expected Behavior:

When enabled, the tab would:

• Use software compositing (Basic Layers instead of WebRender)

• Avoid invoking GPU-decoded video pipelines

• Disable WebGL/WebGPU contexts

• Render using CPU only, avoiding the GPU process entirely

This allows users to prioritize GPU resources for their primary workload, while keeping the browser usable for reference material, chat, or other background activity.

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Why This Matters:

• Prevents browser tabs from disrupting GPU-heavy creative or professional work

• Gives power users precise control over system performance

• Enhances Firefox’s reputation for transparency and customization

• Provides a lightweight fallback rendering mode for lower-end or battery-constrained systems

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Related Context:

• Firefox already offers a global layers.acceleration.disabled setting, but lacks per-tab granularity.

• Chrome has command-line software-only rendering (--disable-gpu), but not per-tab controls either. This could offer a competitive edge over Chromium based browsers in the world of performance management.

• Firefox’s existing multi-process and GPU architecture provides a strong foundation for this control to be added.

[Jon]

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