#400 perf(linux): keep WebKit's DMA-BUF renderer on Wayland

[Anonymous]

Originally created by: kristofferR

Carrier sets WEBKIT_DISABLE_DMABUF_RENDERER=1 on every Wayland session, as a precaution against blank or garbled frames on NVIDIA (#31). Without the DMA-BUF renderer, WebKit paints on the CPU and copies every frame into shared memory. Measured on an RTX 4090 (driver 615.78, WebKitGTK 2.54), hovering in a conversation used 2–3× the CPU of DMA-BUF on, and expensive effects such as nested blurs turned into seconds of lag. With DMA-BUF on, switching chats, hiding and showing the window, and fullscreen all rendered correctly, with no blank, black or garbled frames.

Keep the renderer on by default, and only disable it:

• with NVIDIA's proprietary driver before 555 (the first with Wayland explicit sync), read from /sys/module/nvidia/version;
• in Niri safe mode, or with CARRIER_LINUX_WEBKIT_SAFE_MODE=1.

An explicit WEBKIT_DISABLE_DMABUF_RENDERER value still wins.

The 555 cutoff is a judgment from the driver's explicit-sync history, not a tested boundary. Only one recent NVIDIA setup was tested; anyone who gets a blank window can still use safe mode.

Ref [#31]

[Anonymous]

Originally posted by: kristofferR

⏸️ crq will not request further automated reviews for this pull request.

Reason: CodeRabbit reviews these changes once, in combined PR [#394]

Resume with crq unhold kristofferr/carrier 400.

[Anonymous]

Originally posted by: kristofferR

[!NOTE]
🤖 Claude Opus 5.5 responding on behalf of Kristoffer

@codex review

[Anonymous]

Originally posted by: chatgpt-codex-connector[bot]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request. | Review | Status | Commit | Review trigger | | --- | --- | --- | --- | | 📝 **Code Review** | ✅ **Completed** <relative-time datetime="2026-11-07T20:04:52.512562Z">2026-11-07T20:04:52.512562Z</relative-time> | `eaf9d20` | Manual request |

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[Anonymous]

Originally posted by: chatgpt-codex-connector[bot]

Codex Review: Didn't find any major issues. 🎉

Reviewed commit: eaf9d205b7

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[Anonymous]

Ticket changed by: kristofferR

• status: open --> closed

[Anonymous]

Originally posted by: kristofferR

✅ The administrative hold has been retired because this pull request merged. crq will not request further automated reviews.