UI scenarios, batch 3: plastic enclosure (shell, boss, lip, snap fit), appearance then STEP and 3MF export with the colour, start page sample edited, saved and reopened, two design tabs with their own undo, the S toolbox and V visibility, 3D sketch lines snapped to the model then a pipe along them, canvas inserted and calibrated, section analysis with a joint driven. Harness: until (waits for background work), make_image, widget near a label, checks for files' text, start page, open designs, design name, hidden bodies, canvas width and section. Fixes: Enter in the S command search runs the first match (it read the focus after taking it back); Sketch Palette toggles are checkboxes with their labels (click the text to toggle); a dialog test no longer panics dropping unpainted textures

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/ui-egui/src/dialogs_assembly_tests.rs

@@ -191,7 +191,10 @@ fn ok_click_survives_a_busy_preview() {
     let frame = |app: &mut SolveApp, busy: bool, events: Vec<egui::Event>| {
         app.preview.busy = busy;
         let input = egui::RawInput { screen_rect: Some(screen), events, ..Default::default() };
-        ctx.run_ui(input, |ui| crate::dialogs::show(app, ui.ctx()))
+        let mut out = ctx.run_ui(input, |ui| crate::dialogs::show(app, ui.ctx()));
+        // Nothing is painted: drop the texture changes (an unapplied delta panics on drop).
+        out.textures_delta.clear();
+        out
     };
     frame(&mut app, false, vec![]);
     let out = frame(&mut app, false, vec![]);