Fix up some examples (#3614)

examples/file_dialog/src/main.rs

@@ -6,7 +6,7 @@ fn main() -> Result<(), eframe::Error> {
     env_logger::init(); // Log to stderr (if you run with `RUST_LOG=debug`).
     let options = eframe::NativeOptions {
         viewport: egui::ViewportBuilder::default()
-            .with_inner_size([320.0, 240.0])
+            .with_inner_size([640.0, 240.0]) // wide enough for the drag-drop overlay text
             .with_drag_and_drop(true),
         ..Default::default()
     };