DioxusLabs/dioxus · error

should be run in a context with a `Window` object (dioxus ca

Error message

should be run in a context with a `Window` object (dioxus cannot be run from a web worker)

What it means

`ScrollPosition::scroll_to` - used by the router to restore scroll after navigation - wraps `window.scrollTo(x, y)` in a requestAnimationFrame callback and re-fetches `web_sys::window()` with an expect whose message states the constraint outright: dioxus cannot run from a web worker. In any window-less context (worker, SSR), scroll restoration panics.

Source

Thrown at packages/web/src/history.rs:363

    pub x: f64,
    pub y: f64,
}

impl ScrollPosition {
    pub(crate) fn of_window(window: &Window) -> Self {
        Self {
            x: window.scroll_x().unwrap_or_default(),
            y: window.scroll_y().unwrap_or_default(),
        }
    }

    pub(crate) fn scroll_to(&self, window: Window) {
        let Self { x, y } = *self;
        let f = Closure::wrap(
            Box::new(move || window.scroll_to_with_x_and_y(x, y)) as Box<dyn FnMut()>
        );
        web_sys::window()
            .expect("should be run in a context with a `Window` object (dioxus cannot be run from a web worker)")
            .request_animation_frame(&f.into_js_value().unchecked_into())
            .expect("should register `requestAnimationFrame` OK");
    }
}

pub(crate) fn replace_state_with_url(
    history: &History,
    value: &[f64; 2],
    url: Option<&str>,
) -> Result<(), JsValue> {
    let position = js_sys::Array::new();
    position.push(&JsValue::from(value[0]));
    position.push(&JsValue::from(value[1]));
    history.replace_state_with_url(&position, "", url)
}

pub(crate) fn push_state_and_url(
    history: &History,

View on GitHub (pinned to 393d190a80)

Solutions

1. Keep the router and its scroll restoration on the browser main thread
2. Disable scroll restoration (construct the history with do_scroll_restoration=false) in environments where scrolling cannot work
3. cfg-gate web routing code out of server builds

Example fix

// before: scroll restoration enabled, panics in worker contexts
let history = WebHistory::new(None, true);
// after: disable it where the Window/rAF path cannot run
let history = WebHistory::new(None, false);

fn can_restore_scroll() -> bool {
    web_sys::window().is_some()
}

When it happens

Trigger: Router scroll restoration (or a direct scroll_to call) executing in a web worker; scroll restore triggered after the browsing context is gone.

Common situations: The same misconfigurations that break WebHistory construction: worker-hosted UI, SSR builds linking web renderer code, headless tests touching navigation.

Related errors

• access to `window`
• should register `requestAnimationFrame` OK
• should have access to the Window
• `history` can set scroll restoration
• A router must be present to use navigator

AI-assisted analysis of DioxusLabs/dioxus@393d190a80 (2026-08-16). Data as JSON: /api/errors/e376c0a398b8fd97. Report an issue: GitHub.