diff --git a/backend/sql/version_1.sql b/backend/sql/version_1.sql
index 640fb9e..19b233c 100644
--- a/backend/sql/version_1.sql
+++ b/backend/sql/version_1.sql
@@ -257,9 +257,7 @@ CREATE TABLE [ShoppingEntry] (
     -- In both cases [name], [quantity_value], [quantity_unit] and [Servings] are used to display
     -- the entry instead of [Ingredient] data.
     [ingredient_id] INTEGER,
-
-    -- Can be null when manually added (entry is not linked to a recipe).
-    [recipe_scheduled_id] INTEGER,
+    [recipe_scheduled_id] INTEGER, -- Can be null when manually added.
 
     [is_checked] INTEGER NOT NULL DEFAULT FALSE,
 
@@ -271,7 +269,16 @@ CREATE TABLE [ShoppingEntry] (
 
     CHECK (
         length([name]) <= 255 AND
-        ([is_checked] = TRUE OR [is_checked] = FALSE)
+        ([is_checked] = TRUE OR [is_checked] = FALSE) AND
+        (
+            [recipe_scheduled_id] IS NULL OR
+            (
+                [name] = '' AND
+                [quantity_value] IS NULL AND
+                [quantity_unit] = '' AND
+                [servings] IS NULL
+            )
+        )
     ),
 
     FOREIGN KEY([user_id]) REFERENCES [User]([id]) ON DELETE CASCADE,
diff --git a/backend/templates/calendar.html b/backend/templates/calendar.html
index b75fecb..b46d4bb 100644
--- a/backend/templates/calendar.html
+++ b/backend/templates/calendar.html
@@ -33,7 +33,7 @@
         </div>
     </div>
 
-    <ul class="days">
+    <ul class="weekdays">
         {% let day_names = [
             Sentence::CalendarMondayAbbreviation,
             Sentence::CalendarTuesdayAbbreviation,
@@ -52,10 +52,12 @@
             </li>
         {% endfor %}
 
-        {# The last row may be hidden if 5 rows is enough to display all days. #}
-        {% for i in 0..6 %}
+    </ul>
+
+    <ul class="days">
+        {% for i in 0..5 %}
             {% for j in 0..7 %}
-                {# All days of the current selected month will have the class 'current-month'. #}
+                {# All days of the current selected month will have the class 'current-month' #}
                 <li id="day-grid-{{i}}{{j}}">
                     <div class="number"></div>
                     <div class="scheduled-recipes"></div>
@@ -66,7 +68,11 @@
 
     <div id="hidden-templates-calendar">
         <div class="scheduled-recipe-with-link-and-remove"><a></a>
-            <span class="remove-scheduled-recipe button tooltip">✖<span class="tooltiptext">{{ context.tr.t(Sentence::CalendarUnschedule) }}</span></span>
+            <span class="remove-scheduled-recipe button tooltip">✖
+                <span class="tooltiptext">
+                    {{ context.tr.t(Sentence::CalendarUnschedule) }}
+                </span>
+            </span>
         </div>
 
         <div class="scheduled-recipe"></div>
diff --git a/frontend/src/calendar.rs b/frontend/src/calendar.rs
index dfb97d4..23f5583 100644
--- a/frontend/src/calendar.rs
+++ b/frontend/src/calendar.rs
@@ -167,28 +167,22 @@ pub fn setup(
     EventListener::new(&days, "click", move |event| {
         let target: Element = event.target().unwrap().dyn_into().unwrap();
 
-        // FIXME: Replace by an if let + condition when available in stable.
-        match target.selector_upwards::<Element>(".day") {
-            Some(element) if options.can_select_date => {
-                let first_day = first_grid_day(
-                    state_clone.get_displayed_date(),
-                    options.first_day_of_the_week,
-                );
-                let day_grid_id = element.id();
-                let day_offset = day_grid_id[9..10].parse::<u64>().unwrap() * 7
-                    + day_grid_id[10..11].parse::<u64>().unwrap();
-                state_clone.set_selected_date(first_day + Days::new(day_offset));
-                display_month(
-                    &calendar_clone,
-                    state_clone.clone(),
-                    options,
-                    recipe_scheduler,
-                );
-            }
-            _ => (),
-        }
-
-        if target.class_name().contains("remove-scheduled-recipe") {
+        if target.class_name() == "number" && options.can_select_date {
+            let first_day = first_grid_day(
+                state_clone.get_displayed_date(),
+                options.first_day_of_the_week,
+            );
+            let day_grid_id = target.parent_element().unwrap().id();
+            let day_offset = day_grid_id[9..10].parse::<u64>().unwrap() * 7
+                + day_grid_id[10..11].parse::<u64>().unwrap();
+            state_clone.set_selected_date(first_day + Days::new(day_offset));
+            display_month(
+                &calendar_clone,
+                state_clone.clone(),
+                options,
+                recipe_scheduler,
+            );
+        } else if target.class_name().contains("remove-scheduled-recipe") {
             spawn_local(async move {
                 // Element id format example: "scheduled-recipe-1-2025-05-15".
                 let element_id = target.parent_element().unwrap().id();
@@ -245,6 +239,8 @@ pub fn setup(
     state
 }
 
+const NB_CALENDAR_ROW: u64 = 5;
+
 fn display_month(
     calendar: &Element,
     state: CalendarState,
@@ -272,48 +268,34 @@ fn display_month(
     let first_day = first_grid_day(date, options.first_day_of_the_week);
     let mut current = first_day;
 
-    let nb_of_weeks = {
-        let nb_days_previous_month = if date.month0() == first_day.month0() {
-            0
-        } else {
-            (date.with_day(1).unwrap() - first_day).num_days()
-        };
-        if date.num_days_in_month() + nb_days_previous_month as u8 > 5 * 7 {
-            6
-        } else {
-            5
-        }
-    };
-
-    gloo::console::log!(nb_of_weeks);
-
-    for i in 0..6 {
+    for i in 0..NB_CALENDAR_ROW {
         for j in 0..7 {
             let day_element: Element = by_id(&format!("day-grid-{}{}", i, j));
+
             let day_content: Element = day_element.selector(".number");
+            day_content.set_inner_html(&current.day().to_string());
 
-            if i < nb_of_weeks {
-                day_content.set_inner_html(&current.day().to_string());
+            let mut class_name = String::new();
 
-                let mut classes = vec!["day".to_string()];
-
-                if current.month() == date.month() {
-                    classes.push("current-month".to_string());
+            if current.month() == date.month() {
+                if !class_name.is_empty() {
+                    class_name += " ";
                 }
-                if current == Local::now().date_naive() {
-                    classes.push("today".to_string());
-                }
-
-                if options.can_select_date && current == state.get_selected_date() {
-                    classes.push("selected-day".to_string());
-                }
-
-                day_element.set_class_name(&classes.join(" "));
-            } else {
-                gloo::console::log!("ok");
-                day_element.set_class_name("");
-                day_content.set_inner_html("");
+                class_name += "current-month";
             }
+            if current == Local::now().date_naive() {
+                if !class_name.is_empty() {
+                    class_name += " ";
+                }
+                class_name += "today";
+            }
+            if options.can_select_date && current == state.get_selected_date() {
+                if !class_name.is_empty() {
+                    class_name += " ";
+                }
+                class_name += "selected-day"
+            }
+            day_element.set_class_name(&class_name);
 
             current = current + Days::new(1);
         }
@@ -322,7 +304,7 @@ fn display_month(
     // Load and display scheduled recipes.
     spawn_local(async move {
         let scheduled_recipes = recipe_scheduler
-            .get_scheduled_recipes(first_day, first_day + Days::new(nb_of_weeks * 7))
+            .get_scheduled_recipes(first_day, first_day + Days::new(NB_CALENDAR_ROW * 7))
             .await
             .unwrap();
 
diff --git a/frontend/src/utils.rs b/frontend/src/utils.rs
index e5929d4..ea68d51 100644
--- a/frontend/src/utils.rs
+++ b/frontend/src/utils.rs
@@ -14,10 +14,6 @@ pub trait SelectorExt {
     where
         T: JsCast;
 
-    fn selector_upwards<T>(&self, selector: &str) -> Option<T>
-    where
-        T: JsCast;
-
     fn deep_clone(&self) -> Self;
 }
 
@@ -45,25 +41,6 @@ impl SelectorExt for Element {
             .collect()
     }
 
-    fn selector_upwards<T>(&self, selector: &str) -> Option<T>
-    where
-        T: JsCast,
-    {
-        let mut current = self.clone();
-        // while let Some(parent) = current.parent_element() {
-        loop {
-            if let Ok(true) = current.matches(selector) {
-                return Some(current.dyn_into::<T>().unwrap());
-            }
-
-            if let Some(parent) = current.parent_element() {
-                current = parent;
-            } else {
-                return None;
-            }
-        }
-    }
-
     fn deep_clone(&self) -> Self {
         self.clone_node_with_deep(true)
             .unwrap()