bevyengine/bevy · error

DiagnosticsOverlay has been tempered with. Node must have `l

Error message

DiagnosticsOverlay has been tempered with. Node must have `left` using `Val::Px`.

What it means

Panic in drag_by_header: the dragged overlay's Node.left style is not Val::Px, so dragging cannot update the horizontal position. Only occurs when the overlay node's style was tampered with after creation.

Source

Thrown at crates/bevy_dev_tools/src/diagnostics_overlay.rs:449

    mut event: On<PointerDrag>,
    mut diagnostics_overlays: Query<&mut Node, With<DiagnosticsOverlay>>,
    diagnostics_overlay_headers: Query<&ChildOf, With<DiagnosticsOverlayHeader>>,
) {
    let entity = event.entity;
    if let Ok(child_of) = diagnostics_overlay_headers.get(entity) {
        event.propagate(false);
        let Ok(mut node) = diagnostics_overlays.get_mut(child_of.get()) else {
            panic!("DiagnosticsOverlayHeader has been tempered with. Parent was not a DiagnosticsOverlay.");
        };
        let delta = event.delta;
        let Val::Px(top) = &mut node.top else {
            panic!(
                "DiagnosticsOverlay has been tempered with. Node must have `top` using `Val::Px`."
            );
        };
        *top += delta.y;
        let Val::Px(left) = &mut node.left else {
            panic!(
                "DiagnosticsOverlay has been tempered with. Node must have `left` using `Val::Px`."
            );
        };
        *left += delta.x;
    }
}

fn collapse_on_click_to_header(
    mut event: On<PointerClick>,
    mut diagnostics_overlays: Query<&Children, With<DiagnosticsOverlay>>,
    mut diagnostics_overlay_contents: Query<&mut Node, With<DiagnosticsOverlayContents>>,
    diagnostics_overlay_header: Query<&ChildOf, With<DiagnosticsOverlayHeader>>,
) {
    if event.duration > Duration::from_millis(250) {
        return;
    }

    let entity = event.entity;

View on GitHub (pinned to 396ca72708)

Solutions

1. Keep Node.left as Val::Px on the diagnostics overlay
2. Reset custom styling applied to the overlay node

When it happens

Trigger: Thrown at crates/bevy_dev_tools/src/diagnostics_overlay.rs:449 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of bevyengine/bevy@396ca72708 (2026-08-20). Data as JSON: /api/errors/8c40051092f630a8. Report an issue: GitHub.