zed-industries/zed · error

prompt_for_paths is not supported on the web

Error message

prompt_for_paths is not supported on the web

What it means

Sentinel from the web platform's prompt_for_paths: browsers cannot open native file-open dialogs, so the oneshot channel immediately receives this error. It always fires on the web when the multi-file open prompt API is called — an unimplemented capability, not a runtime fault.

Source

Thrown at crates/gpui_web/src/platform.rs:432

                *self.active_window.borrow_mut() = Some(handle);
                Ok(Box::new(window))
            }
            Err(error) => {
                let canvas: &web_sys::Element = canvas_for_cleanup.as_ref();
                canvas.remove();
                self.window_lifecycle.set(WebWindowLifecycle::Unavailable);
                Err(error)
            }
        }
    }

    fn window_appearance(&self) -> WindowAppearance {
        let Ok(Some(media_query)) = self
            .browser_window
            .match_media("(prefers-color-scheme: dark)")
        else {
            return WindowAppearance::Light;
        };
        if media_query.matches() {
            WindowAppearance::Dark
        } else {
            WindowAppearance::Light
        }
    }

    fn open_url(&self, url: &str) {
        if let Err(error) = self.browser_window.open_with_url(url) {
            log::warn!("Failed to open URL '{url}': {error:?}");
        }
    }

    fn on_open_urls(&self, callback: Box<dyn FnMut(Vec<String>)>) {
        self.callbacks.borrow_mut().open_urls = Some(callback);
    }

    fn register_url_scheme(&self, _url: &str) -> Task<Result<()>> {

View on GitHub (pinned to 9d272b0363)

Solutions

1. Use an HTML input type=file or drag-and-drop based picker on the web platform
2. Gate file-dialog UI behind platform capability checks instead of calling and handling the error
3. Callers can detect this sentinel and degrade gracefully (hide the open-file button)

When it happens

Trigger: Thrown at crates/gpui_web/src/platform.rs:432 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of zed-industries/zed@9d272b0363 (2026-08-20). Data as JSON: /api/errors/57b00bbcd8fc146b. Report an issue: GitHub.