diff --git a/webapp/Pages/Categories/Index.cshtml b/webapp/Pages/Categories/Index.cshtml
index c4375bc..5894e91 100644
--- a/webapp/Pages/Categories/Index.cshtml
+++ b/webapp/Pages/Categories/Index.cshtml
@@ -193,7 +193,7 @@
         <e-grid-loadingIndicator indicatorType="Shimmer"></e-grid-loadingIndicator>
         <e-grid-columns>
             <e-grid-column field="Id" headerText="@Localizer["Id"].Value" isPrimaryKey="true" visible="false"></e-grid-column>
-            <e-grid-column field="Icon" headerText="@Localizer["Icon"].Value" editType="dropdownedit" edit="new { @@params = iconParams }" validationRules="validationRules" allowFiltering="false" width="50"></e-grid-column>
+            <e-grid-column field="Icon" headerText="@Localizer["Icon"].Value" editType="dropdownedit" edit="new { @@params = iconEdit }" validationRules="validationRules" allowFiltering="false" width="50"></e-grid-column>
             <e-grid-column field="Name" headerText="@Localizer["Name"].Value" editType="textboxedit" validationRules="validationRules" minWidth="120" width="140"></e-grid-column>
             <e-grid-column headerText="@Localizer["Commands"].Value" commands="commands" textAlign="Right" width="120"></e-grid-column>
         </e-grid-columns>
@@ -213,18 +213,22 @@
     function actionComplete(args) {
         console.log(args);
         if (args.requestType === "beginEdit" || args.requestType === "add") {
-            var dialog = args.dialog;
+            let dialog = args.dialog;
             dialog.element.style.maxHeight = "1000px";
             dialog.header = args.requestType === "beginEdit" ? "@Localizer["Edit category"].Value" + args.rowData["Name"] : "@Localizer["Add category"].Value";
         }
         if (args.requestType === "delete") {
-            // todo: Show dialog when delete operation is canceled.
-            var canceled = args.cancel;
+            if (args.data != null && args.data.length > 0) {
+                let selectedCategory = args.data[0];
+                fetch("/Categories/NumberOfTransactionsAssociated?id=" + selectedCategory.Id).then(function (result) { return result.json() }).then(function (data) {
+                    if (data > 0) alert("@Localizer["Cancel message"].Value");
+                });
+            }
         }
     }
 
     function toolbarClick(args) {
-        var gridObj = document.getElementById("grid").ej2_instances[0];
+        let gridObj = document.getElementById("grid").ej2_instances[0];
         if (args.item.id === "grid_excelexport") {
             gridObj.showSpinner();
             gridObj.excelExport();
diff --git a/webapp/Pages/Categories/Index.cshtml.cs b/webapp/Pages/Categories/Index.cshtml.cs
index 6fd4db4..9eb37e5 100644
--- a/webapp/Pages/Categories/Index.cshtml.cs
+++ b/webapp/Pages/Categories/Index.cshtml.cs
@@ -34,6 +34,21 @@ public async Task<IActionResult> OnGetAsync() {
             return Page();
         }
 
+        public async Task<IActionResult> OnGetNumberOfTransactionsAssociatedAsync(long id) {
+            if (!(User.Identity?.IsAuthenticated ?? false)) return Redirect("/");
+
+            var user = await GetUserAsync();
+            if (user == null) return Redirect("/");
+
+            var transactionsWithCategory = await _databaseContext.Transactions
+                        .AsNoTracking()
+                        .Where(x => x.UserId == user.Id)
+                        .Where(x => x.CategoryId == id)
+                        .ToListAsync();
+
+            return new JsonResult(transactionsWithCategory.Count);
+        }
+
         public async Task<IActionResult> OnPostDataSourceAsync([FromBody] DataManagerRequest dm) {
             if (!(User.Identity?.IsAuthenticated ?? false)) return Redirect("/");
 
diff --git a/webapp/Pages/Dashboard.cshtml b/webapp/Pages/Dashboard.cshtml
index 21f4c4d..d5f93fe 100644
--- a/webapp/Pages/Dashboard.cshtml
+++ b/webapp/Pages/Dashboard.cshtml
@@ -264,13 +264,13 @@
     }
 
     document.addEventListener("DOMContentLoaded", function() {
-        var lineObj = document.getElementById("lineChart").ej2_instances[0];
+        let lineObj = document.getElementById("lineChart").ej2_instances[0];
         lineObj.refresh();
 
-        var pieObj = document.getElementById("pieChart").ej2_instances[0];
+        let pieObj = document.getElementById("pieChart").ej2_instances[0];
         pieObj.refresh();
 
-        var splineObj = document.getElementById("splineChart").ej2_instances[0];
+        let splineObj = document.getElementById("splineChart").ej2_instances[0];
         splineObj.refresh();
     });
 </script>
diff --git a/webapp/Pages/FixedCosts/Index.cshtml b/webapp/Pages/FixedCosts/Index.cshtml
index b30c9e5..cc9f34d 100644
--- a/webapp/Pages/FixedCosts/Index.cshtml
+++ b/webapp/Pages/FixedCosts/Index.cshtml
@@ -143,7 +143,7 @@
 
     function actionComplete(args) {
         if ((args.requestType === "beginEdit" || args.requestType === "add")) {
-            var dialog = args.dialog;
+            let dialog = args.dialog;
             dialog.element.style.maxHeight = "1000px";
             dialog.header = args.requestType === "beginEdit" ? "@Localizer["Edit transaction"].Value" + args.rowData["Note"] : "@Localizer["Add transaction"].Value";
         }
@@ -197,7 +197,7 @@
     }
 
     function toolbarClick(args) {
-        var gridObj = document.getElementById("grid").ej2_instances[0];
+        let gridObj = document.getElementById("grid").ej2_instances[0];
         if (args.item.id === "grid_excelexport") {
             gridObj.showSpinner();
             gridObj.excelExport();
diff --git a/webapp/Pages/Transactions/Index.cshtml b/webapp/Pages/Transactions/Index.cshtml
index ecb8884..2ba71d0 100644
--- a/webapp/Pages/Transactions/Index.cshtml
+++ b/webapp/Pages/Transactions/Index.cshtml
@@ -52,11 +52,8 @@
     var searchSettings = new string[] { "Note", "CategoryId" };
     var validationRules = new { required = true };
 
-    // todo: date params problem on filtering: time is displayed
     var dateEdit = new DatePicker() {
         Format = Localizer["Date format"].Value,
-        Min = DateOnly.MinValue,
-        Max = DateOnly.MaxValue,
     };
     var statusParams = new List<object>() {
         new { Value = false, Text = Localizer["Pending"].Value },
@@ -66,7 +63,7 @@
         DataSource = statusParams,
         Query = "new ej.data.Query()",
         Fields = new DropDownListFieldSettings() { Value = "Value", Text = "Text" },
-            };
+    };
     var categoryParams = Model.Categories.Select(x => new { Value = x.Id, Text = x.Description });
     var categoryEdit = new DropDownList() {
         DataSource = categoryParams,
diff --git a/webapp/Resources/Pages/Categories/Index.en.resx b/webapp/Resources/Pages/Categories/Index.en.resx
index 64b7d12..abddab1 100644
--- a/webapp/Resources/Pages/Categories/Index.en.resx
+++ b/webapp/Resources/Pages/Categories/Index.en.resx
@@ -120,6 +120,9 @@
   <data name="Add category" xml:space="preserve">
     <value>Add category</value>
   </data>
+  <data name="Cancel message" xml:space="preserve">
+    <value>Cannot be deleted : the category is linked to other transactions.</value>
+  </data>
   <data name="Categories" xml:space="preserve">
     <value>Categories</value>
   </data>
diff --git a/webapp/Resources/Pages/Categories/Index.fr.resx b/webapp/Resources/Pages/Categories/Index.fr.resx
index 3fc191e..346b96d 100644
--- a/webapp/Resources/Pages/Categories/Index.fr.resx
+++ b/webapp/Resources/Pages/Categories/Index.fr.resx
@@ -120,6 +120,9 @@
   <data name="Add category" xml:space="preserve">
     <value>Créer une catégorie</value>
   </data>
+  <data name="Cancel message" xml:space="preserve">
+    <value>Suppression impossible : la cat\u00e9gorie est li\u00e9e \u00e0 d\u0027autres transactions.</value>
+  </data>
   <data name="Categories" xml:space="preserve">
     <value>Catégories</value>
   </data>