fix(gui): default to Slint software renderer so launch survives RDP / no-GL2.0#88
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… no-GL2.0 The shipped 0.1.1 GUI crashes immediately under Remote Desktop (and on VMs / headless / bad-GPU machines): Slint's default femtovg renderer needs OpenGL 2.0, but those environments expose only legacy software GL 1.1, so `MainWindow::new()` fails with "Could not locate glCreateShader symbol", `main` returns Err, and the GUI-subsystem process dies before any window shows — no visible error, just an instant crash. Default `SLINT_BACKEND=winit-software` when unset (escape hatch: `SLINT_BACKEND=winit-femtovg`). This masked-matrix table UI gains nothing from GPU rendering, and a software default covers RDP/VM/driver cases with less logic than RDP-detection. Keep `renderer-software` an explicit slint feature so a future default-features trim can't silently reintroduce the crash. Verified under an RDP session: the window launches with no SLINT_BACKEND set. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Jun 25, 2026
Cuts 0.1.2 to ship the RDP / no-GL2.0 launch fix (#88, 18be430): the GUI now defaults to Slint's software renderer, so the installer no longer crashes on launch under Remote Desktop / VMs / headless GPU. A pushed v0.1.2 tag drives the draft release (verify-version requires tag == janitor-gui crate version). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
The shipped 0.1.1 GUI crashes immediately on launch under Remote Desktop (reproduced on this machine), and the same path will fail on VMs / headless / bad-GPU hosts.
Root cause: Slint's default femtovg renderer requires OpenGL 2.0, but RDP sessions expose only legacy software OpenGL 1.1. So
MainWindow::new()returnsErr("Failed to initialize OpenGL driver: Could not locate glCreateShader symbol"),mainreturnsErr, and the GUI-subsystem process dies before any window shows — no visible error, reads as an instant crash.Confirmed by forcing
SLINT_BACKEND=winit-softwareon the installed 0.1.1 binary → it launches fine.origin/main'sjanitor-gui/src/main.rsis unchanged since thev0.1.1tag and has no backend handling, so the bug is live onmainHEAD.Fix
SLINT_BACKEND=winit-softwarewhen the user hasn't set it (top ofmain(), beforeMainWindow::new()). GPU escape hatch preserved:SLINT_BACKEND=winit-femtovg.renderer-softwarean explicitslintfeature so a futuredefault-featurestrim can't silently reintroduce the crash.Chose software-default over RDP-detection deliberately: it also covers VMs/headless/bad-driver machines with less logic, and this masked-matrix table UI gains nothing from GPU rendering.
Verification
Built and smoke-launched on this branch under an active RDP session with
SLINT_BACKENDunset (JANITOR_MOCK=1): the window stays up. The failing condition no longer crashes.Notes
janitor-guiis the thin, untested-by-design view (ADR 0003); the change is inmain()which tests don't exercise.mainafter merge so RDP/VM users get an unbroken installer. A startup error message box (so future GUI-subsystem init failures are visible) is worth a follow-up but is out of scope here.🤖 Generated with Claude Code