Configuration Overview
Here are all the debug options at a glance:Rendering Options
preview-render
Make niri render the monitors the same way as for a screencast or a screen capture. Useful for previewing the
block-out-from window rule.Options:"screencast""screen-capture"
enable-overlay-planes
Enable direct scanout into overlay planes. May cause frame drops during some animations on some hardware (which is why it is not the default). Direct scanout into the primary plane is always enabled.
disable-cursor-plane
Disable the use of the cursor plane. The cursor will be rendered together with the rest of the frame. Useful to work around driver bugs on specific hardware.
disable-direct-scanout
Disable direct scanout to both the primary plane and the overlay planes.
restrict-primary-scanout-to-matching-format
Restricts direct scanout to the primary plane to when the window buffer exactly matches the composition swapchain format. This flag may prevent unexpected bandwidth changes when going between composition and scanout.
The plan is to make it default in the future, when we implement a way to tell the clients the composition swapchain format. As is, it may prevent some clients (mpv on some machines) from scanning out to the primary plane.
Display Output Options
force-disable-connectors-on-resume
Force-disables all outputs upon resuming niri (TTY switch or waking up from suspend). This causes a modeset/screen blank on all outputs. If niri rendering is corrupted, or monitors don’t light up after a TTY switch, you can try this flag.
render-drm-device
Override the DRM device that niri will use for all rendering. You can set this to make niri use a different primary GPU than the default one.
ignore-drm-device
Available since version 25.11
List DRM devices that niri will ignore. Useful for GPU passthrough when you don’t want niri to open a certain device. Can be specified multiple times.
keep-max-bpc-unchanged
Available since version 25.08
Screen Capture Options
force-pipewire-invalid-modifier
Available since version 25.01
Forces PipeWire screencasting to use the invalid modifier, even when DRM offers more modifiers. Useful for testing the invalid modifier code path that is hit by drivers that don’t support modifiers.
D-Bus and Session Options
dbus-interfaces-in-non-session-instances
Make niri create its D-Bus interfaces even if it’s not running as a
--session. Useful for testing screencasting changes without having to relogin.Performance and Timing Options
wait-for-frame-completion-before-queueing
Wait until every frame is done rendering before handing it over to DRM. Useful for diagnosing certain synchronization and performance problems.
emulate-zero-presentation-time
Emulate zero (unknown) presentation time returned from DRM. This is a thing on NVIDIA proprietary drivers, so this flag can be used to test that niri doesn’t break too hard on those systems.
skip-cursor-only-updates-during-vrr
Available since version 25.08
Skips redrawing the screen from cursor input while variable refresh rate is active. Useful for games where the cursor isn’t drawn internally to prevent erratic VRR shifts in response to cursor movement.
The current implementation has some issues. For example, when there’s nothing redrawing the screen (like a game), the rendering will appear to completely freeze (since cursor movements won’t cause redraws).
Window Management Options
disable-resize-throttling
Available since version 0.1.9
Disable throttling resize events sent to windows. By default, when resizing quickly, a window will only receive the next size once it has made a commit for the previously requested size. This is required for resize transactions to work properly.
disable-transactions
Available since version 0.1.9
Disable transactions (resize and close). By default, windows which must resize together, do resize together. Transactions make niri wait until all windows finish resizing before showing them all on screen in one, synchronized frame.
strict-new-window-focus-policy
Available since version 25.01
Disables heuristic automatic focusing for new windows. Only windows that activate themselves with a valid xdg-activation token will be focused.
honor-xdg-activation-with-invalid-serial
Available since version 25.05
Makes niri honor xdg-activation tokens with invalid serials. By default, niri ignores such tokens to prevent windows from randomly stealing focus.
Widely-used clients such as Discord and Telegram make fresh xdg-activation tokens upon clicking on their tray icon or on their notification. Most of the time, these fresh tokens will have invalid serials, because the app needs to be focused to get a valid serial.This debug flag makes niri honor such tokens, making these widely-used apps get focus when clicking on their tray icon or notification.
deactivate-unfocused-windows
Available since version 25.08
Makes niri drop the Activated state for all unfocused windows. Works around bugs in Chromium- and Electron-based apps that erroneously use the Activated xdg window state instead of keyboard focus.
Some clients (notably, Chromium- and Electron-based, like Teams or Slack) erroneously use the Activated xdg window state instead of keyboard focus for things like deciding whether to send notifications for new messages, or for picking where to show an IME popup. Niri keeps the Activated state on unfocused workspaces and invisible tabbed windows (to reduce unwanted animations), surfacing bugs in these applications.
Monitor and Display Options
keep-laptop-panel-on-when-lid-is-closed
Available since version 0.1.10
By default, niri will disable the internal laptop monitor when the laptop lid is closed. This flag turns off this behavior and will leave the internal laptop monitor on.
disable-monitor-names
Available since version 0.1.10
Disables the make/model/serial monitor names, as if niri fails to read them from the EDID. Use this flag to work around a crash present in 0.1.9 and 0.1.10 when connecting two monitors with matching make/model/serial.
Debug Key Bindings
These are not debug options, but rather key bindings for debugging:toggle-debug-tint
Tints all surfaces green, unless they are being directly scanned out. Useful to check if direct scanout is working.
debug-toggle-opaque-regions
Available since version 0.1.6
Tints regions marked as opaque with blue and the rest of the render elements with red. Useful to check how Wayland surfaces and internal render elements mark their parts as opaque, which is a rendering performance optimization.
debug-toggle-damage
Available since version 0.1.6
Tints damaged regions with red.