wezterm/wezterm · error

to resolve pane selection font

Error message

to resolve pane selection font

What it means

PaneSelect::compute resolves the overlay font via fonts.pane_select_font() (Entity::PaneSelect, same font machinery as the command palette) and .expect("to resolve pane selection font")s the anyhow::Result. Any failure in font selection/loading therefore becomes a panic exactly when the Pane Select overlay is computed, rather than a reportable error, even though compute() returns anyhow::Result and could propagate it.

Source

Thrown at wezterm-gui/src/termwindow/paneselect.rs:61

            element: RefCell::new(None),
            labels: RefCell::new(vec![]),
            selection: RefCell::new(String::new()),
            alphabet,
            mode: args.mode,
            was_zoomed,
            show_pane_ids: args.show_pane_ids,
        }
    }

    fn compute(
        term_window: &mut TermWindow,
        alphabet: &str,
        show_pane_ids: bool,
    ) -> anyhow::Result<(Vec<ComputedElement>, Vec<String>)> {
        let font = term_window
            .fonts
            .pane_select_font()
            .expect("to resolve pane selection font");
        let metrics = RenderMetrics::with_font_metrics(&font.metrics());

        let top_bar_height = if term_window.show_tab_bar && !term_window.config.tab_bar_at_bottom {
            term_window.tab_bar_pixel_height().unwrap()
        } else {
            0.
        };
        let (padding_left, padding_top) = term_window.padding_left_top();
        let border = term_window.get_os_border();
        let top_pixel_y = top_bar_height + padding_top + border.top.get() as f32;

        let panes = term_window.get_panes_to_render();
        let labels =
            crate::overlay::quickselect::compute_labels_for_alphabet(alphabet, panes.len());

        let mut elements = vec![];
        for pos in panes {
            let caption = if show_pane_ids {

View on GitHub (pinned to 3ff7522b96)

Solutions

1. Verify the configured font families exist on the system (fc-list :family / Font Book / Windows font settings)
2. Remove or simplify custom font_rules and window_frame font overrides and retest the overlay
3. Clear wezterm's font cache and restart to re-enumerate installed fonts
4. Reinstall or repair the target font, then reopen pane select

Example fix

// before
let font = term_window.fonts.pane_select_font().expect("to resolve pane selection font");

// after
let font = term_window.fonts.pane_select_font().context("pane select font")?;

// Fail loudly at startup, not when the user opens pane select
fn overlay_fonts_ok(fonts: &wezterm_font::Fonts) -> bool {
    fonts.pane_select_font().is_ok()
}

match term_window.fonts.pane_select_font() {
    Ok(font) => RenderMetrics::with_font_metrics(&font.metrics()),
    Err(err) => {
        log::error!("pane select font unresolved: {err:#}");
        anyhow::bail!("cannot compute pane selector without a font")
    }
}

When it happens

Trigger: Entering pane-select mode on a setup where the overlay font cannot be resolved: missing font family, unsatisfiable font_rules, stale font cache entries pointing at deleted files, or a font that fails to parse under FreeType/CoreText/DirectWrite.

Common situations: Custom fonts uninstalled after the config was written; per-user font installs not visible to the session; heavily customized window_frame/fonts blocks; systems where the font enumeration backend errors out.

Related errors

• to resolve char selection font
• thread terminated without providing a result
• expected to have extents for non-svg image data
• metrics_for_idx: there is no font with idx={font_idx}!?
• RateLimiter capacity to be non-zero

AI-assisted analysis of wezterm/wezterm@3ff7522b96 (2026-08-20). Data as JSON: /api/errors/6c84a903e8042c63. Report an issue: GitHub.