Linux: launch on NVIDIA + Wayland; webAppUrl for "call in browser" #23

2026-09-27T16:57:40-04:00

jared commented

2026-09-27 16:57:40 -04:00

1. NVIDIA + Wayland: the app never opened

Reported on CachyOS (KDE Wayland, RTX 3070, driver 615.71.09, webkit2gtk 2.52.6):

natively, GDK dies with Error 71 (Protocol error) dispatching to Wayland display
with GDK_BACKEND=x11, WebKit fails with Failed to create GBM buffer of size … Invalid argument
WEBKIT_DISABLE_DMABUF_RENDERER=1 GDK_BACKEND=x11 cinny works normally.

gpu_workarounds::apply() runs first thing in main(), before GTK/WebKit start. Only when the NVIDIA driver is loaded (/proc/driver/nvidia/version or /sys/module/nvidia):

It sets WEBKIT_DISABLE_DMABUF_RENDERER=1.
On a Wayland session with XWayland available (DISPLAY set), it also sets GDK_BACKEND=x11. Without XWayland it stays on Wayland, since there's nothing to fall back to.
Values the user already set win, and LOTUS_NO_GPU_WORKAROUNDS=1 turns it all off, for when a newer driver or WebKit fixes this.
It logs what it set to stderr.

Non-NVIDIA systems are untouched: DMA-BUF stays on, for performance.

Tests: 7 unit tests for the decision:

nothing happens without NVIDIA
NVIDIA on Wayland gets both variables
NVIDIA on an X11 session gets only the DMA-BUF one
Wayland without XWayland stays on Wayland
XDG_SESSION_TYPE=wayland is detected
the user's own values win
the opt-out works.

cargo test passes and clippy is clean for the new module.

Not tested here: there's no NVIDIA GPU on the build machine. The workaround is exactly the reporter's, so the real check is the reporter launching the next Arch build with no environment variables set.

2. `webAppUrl` in config.json

https://chat.lotusguild.org, used by cinny's "Open in browser" call fallback (cinny calls-open-in-browser, cinny-desktop #21).

Notes

Release CI only runs on main. Merging this ships in the next desktop release; the web part arrives through the nightly cinny submodule catch-up once the cinny PR is merged.
The "fall back automatically when Wayland init fails" part of the report: GDK aborts on protocol error 71 mid-run rather than returning an error, so we can't catch it in-process. Choosing XWayland up front on NVIDIA avoids it.

🤖 Generated with Claude Code

https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

## 1. NVIDIA + Wayland: the app never opened Reported on CachyOS (KDE Wayland, RTX 3070, driver 615.71.09, webkit2gtk 2.52.6): - natively, GDK dies with `Error 71 (Protocol error) dispatching to Wayland display` - with `GDK_BACKEND=x11`, WebKit fails with `Failed to create GBM buffer of size … Invalid argument` - `WEBKIT_DISABLE_DMABUF_RENDERER=1 GDK_BACKEND=x11 cinny` works normally. `gpu_workarounds::apply()` runs first thing in `main()`, before GTK/WebKit start. Only when the NVIDIA driver is loaded (`/proc/driver/nvidia/version` or `/sys/module/nvidia`): - It sets `WEBKIT_DISABLE_DMABUF_RENDERER=1`. - On a Wayland session with XWayland available (`DISPLAY` set), it also sets `GDK_BACKEND=x11`. Without XWayland it stays on Wayland, since there's nothing to fall back to. - Values the user already set win, and `LOTUS_NO_GPU_WORKAROUNDS=1` turns it all off, for when a newer driver or WebKit fixes this. - It logs what it set to stderr. Non-NVIDIA systems are untouched: DMA-BUF stays on, for performance. **Tests:** 7 unit tests for the decision: - nothing happens without NVIDIA - NVIDIA on Wayland gets both variables - NVIDIA on an X11 session gets only the DMA-BUF one - Wayland without XWayland stays on Wayland - `XDG_SESSION_TYPE=wayland` is detected - the user's own values win - the opt-out works. `cargo test` passes and clippy is clean for the new module. **Not tested here:** there's no NVIDIA GPU on the build machine. The workaround is exactly the reporter's, so the real check is the reporter launching the next Arch build with no environment variables set. ## 2. `webAppUrl` in config.json `https://chat.lotusguild.org`, used by cinny's "Open in browser" call fallback (cinny `calls-open-in-browser`, cinny-desktop #21). ## Notes - Release CI only runs on `main`. Merging this ships in the next desktop release; the web part arrives through the nightly cinny submodule catch-up once the cinny PR is merged. - The "fall back automatically when Wayland init fails" part of the report: GDK aborts on protocol error 71 mid-run rather than returning an error, so we can't catch it in-process. Choosing XWayland up front on NVIDIA avoids it. 🤖 Generated with [Claude Code](https://claude.com/claude-code) https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

jared added 1 commit 2026-09-27 16:57:40 -04:00

fix(linux): launch on NVIDIA + Wayland; config webAppUrl for "call in browser" df760abdc7

NVIDIA + Wayland (reported on CachyOS/KDE, driver 615.71, webkit2gtk
2.52.6): no window. GDK dies with "Error 71 (Protocol error) dispatching to
Wayland display"; forced onto XWayland, WebKit's DMA-BUF renderer then fails
with "Failed to create GBM buffer … Invalid argument". The reporter's
workaround, WEBKIT_DISABLE_DMABUF_RENDERER=1 GDK_BACKEND=x11, runs fine.

gpu_workarounds::apply(), first thing in main() (before GTK/WebKit init):
when the NVIDIA driver is loaded (/proc/driver/nvidia/version or
/sys/module/nvidia), set WEBKIT_DISABLE_DMABUF_RENDERER=1, and on a Wayland
session that has XWayland (DISPLAY set) also GDK_BACKEND=x11. Values the user
already set win; LOTUS_NO_GPU_WORKAROUNDS=1 turns it all off. Logs what it
set to stderr. Non-NVIDIA systems are untouched. Unit tests for the decision.

config.json: webAppUrl = https://chat.lotusguild.org, used by the web client
(cinny `calls-open-in-browser`) to send calls this WebKitGTK build can't make
to the web app in the browser.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

jared merged commit 5b4528e4e5 into main

2026-09-27 17:10:52 -04:00

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Reference: LotusGuild/cinny-desktop#23

Linux: launch on NVIDIA + Wayland; webAppUrl for "call in browser" #23

1. NVIDIA + Wayland: the app never opened

2. webAppUrl in config.json

Notes

2. `webAppUrl` in config.json