diff --git a/src/aiidalab_qe_vibroscopy/utils/euphonic/__init__.py b/src/aiidalab_qe_vibroscopy/utils/euphonic/__init__.py
index 9552900..0d60410 100644
--- a/src/aiidalab_qe_vibroscopy/utils/euphonic/__init__.py
+++ b/src/aiidalab_qe_vibroscopy/utils/euphonic/__init__.py
@@ -18,6 +18,34 @@
 
 ###### START for detached app:
 
+# spinner for waiting time (supercell estimations)
+spinner_html = """
+<style>
+@keyframes spin {
+  0% { transform: rotate(0deg); }
+  100% { transform: rotate(360deg); }
+}
+
+.spinner {
+  display: inline-block;
+  width: 15px;
+  height: 15px;
+}
+
+.spinner div {
+  width: 100%;
+  height: 100%;
+  border: 4px solid #f3f3f3;
+  border-top: 4px solid #3498db;
+  border-radius: 50%;
+  animation: spin 1s linear infinite;
+}
+</style>
+<div class="spinner">
+  <div></div>
+</div>
+"""
+
 
 # Upload buttons
 class UploadPhonopyYamlWidget(ipw.FileUpload):
@@ -166,6 +194,11 @@ def __init__(self, mode="aiidalab-qe app plugin", fc=None, q_path=None):
         )
         self.plot_button.on_click(self._on_first_plot_button_clicked)
 
+        self.loading_widget = ipw.HTML(
+            value=spinner_html,
+        )
+        self.loading_widget.layout.display = "none"
+
         if self.mode == "aiidalab-qe app plugin":
             self.upload_widget.layout.display = "none"
             self.plot_button.disabled = False
@@ -177,6 +210,7 @@ def __init__(self, mode="aiidalab-qe app plugin", fc=None, q_path=None):
             children=[
                 self.upload_widget,
                 self.plot_button,
+                self.loading_widget,
                 self.tab_widget,
             ],
         )
@@ -232,6 +266,9 @@ def _generate_force_constants(
     def _on_first_plot_button_clicked(self, change=None):
         # It creates the widgets
         self.plot_button.layout.display = "none"
+
+        self.loading_widget.layout.display = "block"
+
         self.fc = self._generate_force_constants()
 
         # I first initialise this widget, to then have the 0K ref for the other two.
@@ -247,6 +284,8 @@ def _on_first_plot_button_clicked(self, change=None):
             ),
         )
 
+        self.loading_widget.layout.display = "none"
+
         self.tab_widget.layout.display = "block"
 
 
diff --git a/src/aiidalab_qe_vibroscopy/utils/euphonic/intensity_maps.py b/src/aiidalab_qe_vibroscopy/utils/euphonic/intensity_maps.py
index 6946f2c..09d6d08 100644
--- a/src/aiidalab_qe_vibroscopy/utils/euphonic/intensity_maps.py
+++ b/src/aiidalab_qe_vibroscopy/utils/euphonic/intensity_maps.py
@@ -299,6 +299,21 @@ def produce_bands_weigthed_data(
         x_tick_labels = get_qpoint_labels(
             modes.qpts, cell=modes.crystal.to_spglib_cell()
         )
+
+    # duplication from euphonic/cli/utils.py
+    if args.emin is None:
+        # Subtract small amount from min frequency - otherwise due to unit
+        # conversions binning of this frequency can vary with different
+        # architectures/lib versions, making it difficult to test
+        emin_room = 1e-5 * ureg("meV").to(modes.frequencies.units).magnitude
+        args.emin = min(np.min(modes.frequencies.magnitude - emin_room), 0.0)
+    if args.emax is None:
+        args.emax = np.max(modes.frequencies.magnitude) * 1.05
+    if args.emin >= args.emax:
+        raise ValueError(
+            "Maximum energy ({args.emax}) should be greater than minimum ({args.emin}). "
+        )
+
     modes.frequencies_unit = args.energy_unit
     ebins = _get_energy_bins(modes, args.ebins + 1, emin=args.e_min, emax=args.e_max)