diff --git a/package.json b/package.json
index 26633c2..4736915 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,7 @@
     "lists:index": "node scripts/generate-list-indexes.mjs",
     "lint": "eslint .",
     "check": "node --check server.mjs && node --check vite.config.js && npm run lint && npm run lists:index && npm test && npm run build",
+    "check:full": "npm run check && npm run test:e2e",
     "test": "node --test",
     "test:e2e": "playwright test"
   },
diff --git a/tests/static-toolboxes.test.mjs b/tests/static-toolboxes.test.mjs
index a2aaae7..46c6096 100644
--- a/tests/static-toolboxes.test.mjs
+++ b/tests/static-toolboxes.test.mjs
@@ -180,6 +180,12 @@ test("toolbox module registry and modules expose expected behavior", async () =>
   assert.match(moduleRegistry, /export function AddToolControls/);
   assert.match(moduleRegistry, /export function ToolboxModules/);
   assert.match(moduleRegistry, /MODULE_COMPONENTS/);
+  assert.match(moduleRegistry, /lazy\(\(\) => import\("\.\/CombosModule\.jsx"\)/);
+  assert.match(moduleRegistry, /lazy\(\(\) => import\("\.\/CalendarModule\.jsx"\)/);
+  assert.match(moduleRegistry, /lazy\(\(\) => import\("\.\/GoalTreeModule\.jsx"\)/);
+  assert.match(moduleRegistry, /lazy\(\(\) => import\("\.\/EquipmentPlannerModule\.jsx"\)/);
+  assert.match(moduleRegistry, /Suspense fallback=\{<ModuleLoadingFallback label=\{label\} \/>\}/);
+  assert.match(moduleRegistry, /LAZY_MODULE_TYPES/);
   assert.match(moduleRegistry, /notepad:/);
   assert.match(moduleRegistry, /checklist:/);
   assert.match(moduleRegistry, /images:/);
@@ -365,6 +371,7 @@ test("toolbox module registry and modules expose expected behavior", async () =>
   assert.match(goalTreeModule, /GoalTreeIconPicker/);
   assert.match(goalTreeModule, /GoalTreeContentEditor/);
   assert.match(goalTreeModule, /GoalTreeNodeContentPreview/);
+  assert.doesNotMatch(goalTreeModule, /\.slice\(0, 3\)/);
   assert.match(goalTreeModule, /GoalTreeChecklistInlineControl/);
   assert.match(goalTreeModule, /GoalTreeStepLeafControl/);
   assert.match(goalTreeModule, /GoalTreePrerequisitePicker/);
diff --git a/tests/toolbox-modules.test.mjs b/tests/toolbox-modules.test.mjs
index 5679067..38416e6 100644
--- a/tests/toolbox-modules.test.mjs
+++ b/tests/toolbox-modules.test.mjs
@@ -5,6 +5,7 @@ import { evaluateTableCell } from "../website/src/features/toolboxes/modules/tab
 import { exportModuleText, importModuleText, parseColonImportLines } from "../website/src/features/toolboxes/modules/textImport.js";
 import { buildInsertedMixTagValue, normalizeMixTagSpacing, normalizeMixTagText, removeMixTagAtOffset, tokenizeMixTagValue } from "../website/src/utils/mixTagsInputUtils.js";
 import { calculateGoalTreeFormula, evaluateGoalTreeNodes } from "../website/src/features/toolboxes/modules/goalTreeUtils.js";
+import { getMonthOccurrenceSegments, getWeekGridLayout, getWeekMinutePosition, layoutConcurrentOccurrences } from "../website/src/features/toolboxes/modules/calendarLayout.js";
 import { getTimePatternRecurrenceMs, getTimePatternTargetMs } from "../website/src/features/toolboxes/modules/timerUtils.js";
 import { compactModuleDataForStorage, createToolboxExportPayload, normalizeCalculatorData, normalizeChecklistData, normalizeCombosData, normalizeCountersData, normalizeEquipmentPlannerData, normalizeGoalTreeData, normalizeImageAnnotationData, normalizeLinksData, normalizeModuleOrder, normalizeNotepadData, normalizeTableData, normalizeTaskPlannerData, normalizeTimerData, normalizeToolbox, normalizeUrl, summarizeEquipmentPlannerData } from "../website/src/features/toolboxes/storage/toolboxStorage.js";
 import { applyGroupedReorderOperation, completeGroupOrder, getBoundaryItemId, getGroupedEntries, moveGroupOrder, moveGroupOrderToEnd, moveGroupOrderToStart, moveItem, moveItemGroup } from "../website/src/hooks/useGroupedReorder.js";
@@ -150,6 +151,41 @@ test("text exchange imports table TSV and calculator hierarchy", () => {
   assert.equal(calculatorImport.data.entries[1].formula, "base*5");
 });
 
+test("calendar layout keeps week compaction and overlapping lanes deterministic", () => {
+  const base = new Date(2026, 0, 5, 8, 0, 0, 0).getTime();
+  const occurrences = [
+    { id: "a", startMs: base, endMs: base + 60 * 60000, event: { startMinutes: 8 * 60, endMinutes: 9 * 60 } },
+    { id: "b", startMs: base + 30 * 60000, endMs: base + 90 * 60000, event: { startMinutes: 8 * 60 + 30, endMinutes: 9 * 60 + 30 } }
+  ];
+  const layout = getWeekGridLayout(occurrences, true);
+  assert.ok(layout.rows.some((row) => row.type === "hidden"));
+  assert.equal(getWeekMinutePosition(layout, 8 * 60), layout.hourTopPx[8]);
+  assert.equal(getWeekMinutePosition(layout, 24 * 60), layout.totalHeightPx);
+  assert.deepEqual(layoutConcurrentOccurrences(occurrences).map((occurrence) => [occurrence.id, occurrence.lane, occurrence.laneCount]), [
+    ["a", 0, 2],
+    ["b", 1, 2]
+  ]);
+});
+
+test("calendar month layout splits bars on week boundaries and shares lanes", () => {
+  const days = Array.from({ length: 14 }, (_, index) => ({
+    date: new Date(2026, 0, 5 + index),
+    inMonth: true
+  }));
+  const firstStart = days[4].date.getTime();
+  const secondStart = days[5].date.getTime();
+  const segments = getMonthOccurrenceSegments(days, [
+    { id: "a", startMs: firstStart, endMs: days[9].date.getTime(), event: {} },
+    { id: "b", startMs: secondStart, endMs: days[7].date.getTime(), event: {} }
+  ]);
+  assert.deepEqual(segments.map((segment) => [segment.occurrence.id, segment.lane, segment.startIndex, segment.endIndex]), [
+    ["a", 0, 4, 6],
+    ["a", 0, 7, 8],
+    ["b", 1, 5, 6]
+  ]);
+  assert.equal(segments[0].laneCount, 2);
+});
+
 test("goal tree text exchange imports formulas and hierarchy", () => {
   const context = createTextImportContext();
   const imported = importModuleText("goalTree", "- Breuvage de rage x10\n  - Élixir de destruction = base * 3\n    - Poudre de flamme x5\n    - Sève de cèdre x7\n  - Catalyseur magique x10", context);
diff --git a/website/src/features/toolboxes/modules/CalendarModule.jsx b/website/src/features/toolboxes/modules/CalendarModule.jsx
index f3e4626..72fd63f 100644
--- a/website/src/features/toolboxes/modules/CalendarModule.jsx
+++ b/website/src/features/toolboxes/modules/CalendarModule.jsx
@@ -25,16 +25,18 @@ import {
   parseLocalDateKey,
   timeValueToMinutes
 } from "./calendarUtils.js";
+import {
+  HOUR_HALF_SLOT_COUNT,
+  WEEK_COMPACT_EVENT_HEIGHT,
+  WEEK_SLOT_COUNT,
+  WEEKDAY_LABELS,
+  getMonthOccurrenceSegments,
+  getWeekGridLayout,
+  getWeekMinutePosition,
+  layoutConcurrentOccurrences
+} from "./calendarLayout.js";
 import { ALERT_MODES } from "./timerOptions.js";
 
-const DAY_HOUR_COUNT = 24;
-const HOUR_HALF_SLOT_COUNT = 2;
-const WEEK_SLOT_COUNT = DAY_HOUR_COUNT * HOUR_HALF_SLOT_COUNT;
-const WEEK_HOUR_ROW_HEIGHT = 27;
-const WEEK_HIDDEN_ROW_HEIGHT = 20;
-const WEEK_COMPACT_EVENT_HEIGHT = WEEK_HOUR_ROW_HEIGHT / HOUR_HALF_SLOT_COUNT;
-const WEEKDAY_LABELS = ["lundi", "mardi", "mercredi", "jeudi", "vendredi", "samedi", "dimanche"];
-
 const CALENDAR_COLOR_VALUES = {
   violet: "#8b5cf6",
   gold: "#f6c453",
@@ -163,149 +165,6 @@ function normalizeDraftAlertOffsets(value) {
   return offsets.sort((a, b) => b - a);
 }
 
-function occurrencesOverlap(first, second) {
-  const firstEnd = first.endMs > first.startMs ? first.endMs : first.startMs + WEEK_SLOT_MINUTES * 60000;
-  const secondEnd = second.endMs > second.startMs ? second.endMs : second.startMs + WEEK_SLOT_MINUTES * 60000;
-  return first.startMs < secondEnd && second.startMs < firstEnd;
-}
-
-function layoutConcurrentOccurrences(dayOccurrences) {
-  const laneEndMs = [0, 0];
-  return dayOccurrences
-    .map((occurrence, index, all) => {
-      const lane = laneEndMs[0] <= occurrence.startMs ? 0 : 1;
-      laneEndMs[lane] = occurrence.endMs > occurrence.startMs ? occurrence.endMs : occurrence.startMs + WEEK_SLOT_MINUTES * 60000;
-      const overlaps = all.some((item, itemIndex) => itemIndex !== index && occurrencesOverlap(occurrence, item));
-      return { ...occurrence, lane, laneCount: overlaps ? 2 : 1 };
-    });
-}
-
-function eventMinutesRange(occurrence) {
-  const startMinutes = Math.max(0, Math.min(24 * 60 - 1, Number(occurrence.event.startMinutes) || 0));
-  const endMinutes = occurrence.event.endMinutes && occurrence.event.endMinutes > startMinutes
-    ? occurrence.event.endMinutes
-    : startMinutes + WEEK_SLOT_MINUTES;
-  return {
-    startMinutes,
-    endMinutes: Math.max(startMinutes + WEEK_SLOT_MINUTES, Math.min(24 * 60, endMinutes))
-  };
-}
-
-function getWeekGridLayout(occurrences, hideEmptyHours) {
-  const occupiedHours = Array.from({ length: DAY_HOUR_COUNT }, () => false);
-  occurrences.forEach((occurrence) => {
-    const { startMinutes, endMinutes } = eventMinutesRange(occurrence);
-    for (let hourIndex = 0; hourIndex < DAY_HOUR_COUNT; hourIndex += 1) {
-      const hourStart = hourIndex * 60;
-      const hourEnd = hourStart + 60;
-      if (startMinutes < hourEnd && endMinutes > hourStart) occupiedHours[hourIndex] = true;
-    }
-  });
-
-  const rows = [];
-  let hourIndex = 0;
-  while (hourIndex < DAY_HOUR_COUNT) {
-    if (!hideEmptyHours || occupiedHours[hourIndex]) {
-      rows.push({ type: "hour", hourIndex });
-      hourIndex += 1;
-      continue;
-    }
-
-    const runStart = hourIndex;
-    while (hourIndex < DAY_HOUR_COUNT && !occupiedHours[hourIndex]) hourIndex += 1;
-    const runEnd = hourIndex - 1;
-    if (runEnd - runStart + 1 >= 3) {
-      rows.push({ type: "hour", hourIndex: runStart });
-      rows.push({ type: "hidden", startHour: runStart + 1, endHour: runEnd - 1 });
-      rows.push({ type: "hour", hourIndex: runEnd });
-    } else {
-      for (let visibleHour = runStart; visibleHour <= runEnd; visibleHour += 1) rows.push({ type: "hour", hourIndex: visibleHour });
-    }
-  }
-
-  const hourTopPx = {};
-  const hiddenRanges = [];
-  let topPx = 0;
-  rows.forEach((row) => {
-    row.topPx = topPx;
-    if (row.type === "hidden") {
-      hiddenRanges.push(row);
-      topPx += WEEK_HIDDEN_ROW_HEIGHT;
-      return;
-    }
-    hourTopPx[row.hourIndex] = topPx;
-    topPx += WEEK_HOUR_ROW_HEIGHT;
-  });
-
-  return {
-    rows,
-    hourTopPx,
-    hiddenRanges,
-    totalHeightPx: topPx,
-    gridTemplateRows: rows.map((row) => `${row.type === "hidden" ? WEEK_HIDDEN_ROW_HEIGHT : WEEK_HOUR_ROW_HEIGHT}px`).join(" ")
-  };
-}
-
-function getWeekMinutePosition(layout, minutes) {
-  const boundedMinutes = Math.max(0, Math.min(24 * 60, minutes));
-  const hourIndex = Math.min(DAY_HOUR_COUNT - 1, Math.floor(boundedMinutes / 60));
-  const visibleHourTop = layout.hourTopPx[hourIndex];
-  if (visibleHourTop !== undefined) {
-    return visibleHourTop + ((boundedMinutes - hourIndex * 60) / 60) * WEEK_HOUR_ROW_HEIGHT;
-  }
-
-  const hiddenRange = layout.hiddenRanges.find((range) => hourIndex >= range.startHour && hourIndex <= range.endHour);
-  if (hiddenRange) {
-    const rangeStartMinutes = hiddenRange.startHour * 60;
-    const rangeMinutes = (hiddenRange.endHour - hiddenRange.startHour + 1) * 60;
-    return hiddenRange.topPx + ((boundedMinutes - rangeStartMinutes) / rangeMinutes) * WEEK_HIDDEN_ROW_HEIGHT;
-  }
-
-  return layout.totalHeightPx;
-}
-
-function getMonthOccurrenceSegments(days, occurrences) {
-  const laneUsage = days.map(() => [false, false, false]);
-  const segments = occurrences.flatMap((occurrence) => {
-    const coveredIndexes = days
-      .map((day, index) => {
-        const dayStart = day.date.getTime();
-        const dayEnd = addDays(day.date, 1).getTime();
-        const occurrenceEnd = Math.max(occurrence.endMs, occurrence.startMs + WEEK_SLOT_MINUTES * 60000);
-        return day.inMonth && occurrence.startMs < dayEnd && occurrenceEnd > dayStart ? index : -1;
-      })
-      .filter((index) => index >= 0);
-    if (!coveredIndexes.length) return [];
-
-    const lane = [0, 1, 2].find((candidate) => coveredIndexes.every((index) => !laneUsage[index][candidate])) ?? 2;
-    coveredIndexes.forEach((index) => {
-      laneUsage[index][lane] = true;
-    });
-
-    const segments = [];
-    let segmentStart = coveredIndexes[0];
-    let previous = coveredIndexes[0];
-    coveredIndexes.slice(1).forEach((index) => {
-      const sameWeekRow = Math.floor(index / WEEKDAY_LABELS.length) === Math.floor(previous / WEEKDAY_LABELS.length);
-      if (index === previous + 1 && sameWeekRow) {
-        previous = index;
-        return;
-      }
-      segments.push({ occurrence, lane, startIndex: segmentStart, endIndex: previous });
-      segmentStart = index;
-      previous = index;
-    });
-    segments.push({ occurrence, lane, startIndex: segmentStart, endIndex: previous });
-    return segments;
-  });
-  return segments.map((segment) => {
-    const laneCount = Math.max(1, ...segments
-      .filter((item) => item.startIndex <= segment.endIndex && item.endIndex >= segment.startIndex)
-      .map((item) => item.lane + 1));
-    return { ...segment, laneCount };
-  });
-}
-
 export function CalendarModule({ toolboxId, moduleId, context, editing = false, setEditing, textExchangeOpen }) {
   const data = context.normalizeCalendarData(context.getModuleData(toolboxId, moduleId, { initialized: false, viewMode: "week", events: [] }));
   const textContent = context.moduleText?.calendar || {};
diff --git a/website/src/features/toolboxes/modules/GoalTreeModule.jsx b/website/src/features/toolboxes/modules/GoalTreeModule.jsx
index e344bf0..0923d03 100644
--- a/website/src/features/toolboxes/modules/GoalTreeModule.jsx
+++ b/website/src/features/toolboxes/modules/GoalTreeModule.jsx
@@ -1,5 +1,5 @@
 // Rôle : fournit l'outil arbre d'objectifs avec quantités, formules, resets et échange texte.
-import { useEffect, useLayoutEffect, useMemo, useRef, useState } from "react";
+import { useCallback, useEffect, useLayoutEffect, useMemo, useRef, useState } from "react";
 import { CompactDropdown } from "../../../components/CompactDropdown.jsx";
 import { DiagramConnectors } from "../../../components/DiagramConnectors.jsx";
 import { Icon } from "../../../components/Icon.jsx";
@@ -173,6 +173,9 @@ export function GoalTreeModule({ toolboxId, moduleId, context, editing, setEditi
     { id: "advanced", label: textContent.advancedTab || "Avancé", icon: "settings" }
   ];
   const parentMap = useMemo(() => getGoalTreeParentMap(evaluatedNodes), [evaluatedNodes]);
+  const save = useCallback((nextData) => {
+    context.setModuleData(toolboxId, moduleId, nextData, "goalTree");
+  }, [context, moduleId, toolboxId]);
   const reorder = useGroupedReorder({
     namespace: "goal-tree",
     items: evaluatedNodes,
@@ -186,7 +189,7 @@ export function GoalTreeModule({ toolboxId, moduleId, context, editing, setEditi
   useEffect(() => {
     const resetData = applyGoalTreeDueResets(data, Date.now());
     if (resetData !== data) save(resetData);
-  });
+  }, [data, save]);
 
   useEffect(() => {
     if (!selectedNodeId && data.nodes[0]) setSelectedNodeId(data.nodes[0].id);
@@ -243,10 +246,6 @@ export function GoalTreeModule({ toolboxId, moduleId, context, editing, setEditi
     };
   }, [connectorTopologyKey, editing, textExchangeOpen, viewScale]);
 
-  function save(nextData) {
-    context.setModuleData(toolboxId, moduleId, nextData, "goalTree");
-  }
-
   function addNode(parentId = "") {
     const parent = data.nodes.find((node) => node.id === parentId);
     const node = {
@@ -990,7 +989,7 @@ function GoalTreeStepLeafControl({ node, textContent, onChange }) {
 }
 
 function GoalTreeNodeContentPreview({ node, editing, textContent, onAddContentItem, onUpdateItem }) {
-  const items = (node.items || []).slice(0, 3);
+  const items = node.items || [];
   return (
     <span className="goal-tree-node-content-preview">
       {items.map((item) => (
diff --git a/website/src/features/toolboxes/modules/calendarLayout.js b/website/src/features/toolboxes/modules/calendarLayout.js
new file mode 100644
index 0000000..1f500b2
--- /dev/null
+++ b/website/src/features/toolboxes/modules/calendarLayout.js
@@ -0,0 +1,153 @@
+// Rôle : calcule les constantes et positions de layout pour les vues calendrier.
+import { WEEK_SLOT_MINUTES, addDays } from "./calendarUtils.js";
+
+export const DAY_HOUR_COUNT = 24;
+export const HOUR_HALF_SLOT_COUNT = 2;
+export const WEEK_SLOT_COUNT = DAY_HOUR_COUNT * HOUR_HALF_SLOT_COUNT;
+export const WEEK_HOUR_ROW_HEIGHT = 27;
+export const WEEK_HIDDEN_ROW_HEIGHT = 20;
+export const WEEK_COMPACT_EVENT_HEIGHT = WEEK_HOUR_ROW_HEIGHT / HOUR_HALF_SLOT_COUNT;
+export const WEEKDAY_LABELS = ["lundi", "mardi", "mercredi", "jeudi", "vendredi", "samedi", "dimanche"];
+
+function occurrencesOverlap(first, second) {
+  const firstEnd = first.endMs > first.startMs ? first.endMs : first.startMs + WEEK_SLOT_MINUTES * 60000;
+  const secondEnd = second.endMs > second.startMs ? second.endMs : second.startMs + WEEK_SLOT_MINUTES * 60000;
+  return first.startMs < secondEnd && second.startMs < firstEnd;
+}
+
+export function layoutConcurrentOccurrences(dayOccurrences) {
+  const laneEndMs = [0, 0];
+  return dayOccurrences
+    .map((occurrence, index, all) => {
+      const lane = laneEndMs[0] <= occurrence.startMs ? 0 : 1;
+      laneEndMs[lane] = occurrence.endMs > occurrence.startMs ? occurrence.endMs : occurrence.startMs + WEEK_SLOT_MINUTES * 60000;
+      const overlaps = all.some((item, itemIndex) => itemIndex !== index && occurrencesOverlap(occurrence, item));
+      return { ...occurrence, lane, laneCount: overlaps ? 2 : 1 };
+    });
+}
+
+function eventMinutesRange(occurrence) {
+  const startMinutes = Math.max(0, Math.min(24 * 60 - 1, Number(occurrence.event.startMinutes) || 0));
+  const endMinutes = occurrence.event.endMinutes && occurrence.event.endMinutes > startMinutes
+    ? occurrence.event.endMinutes
+    : startMinutes + WEEK_SLOT_MINUTES;
+  return {
+    startMinutes,
+    endMinutes: Math.max(startMinutes + WEEK_SLOT_MINUTES, Math.min(24 * 60, endMinutes))
+  };
+}
+
+export function getWeekGridLayout(occurrences, hideEmptyHours) {
+  const occupiedHours = Array.from({ length: DAY_HOUR_COUNT }, () => false);
+  occurrences.forEach((occurrence) => {
+    const { startMinutes, endMinutes } = eventMinutesRange(occurrence);
+    for (let hourIndex = 0; hourIndex < DAY_HOUR_COUNT; hourIndex += 1) {
+      const hourStart = hourIndex * 60;
+      const hourEnd = hourStart + 60;
+      if (startMinutes < hourEnd && endMinutes > hourStart) occupiedHours[hourIndex] = true;
+    }
+  });
+
+  const rows = [];
+  let hourIndex = 0;
+  while (hourIndex < DAY_HOUR_COUNT) {
+    if (!hideEmptyHours || occupiedHours[hourIndex]) {
+      rows.push({ type: "hour", hourIndex });
+      hourIndex += 1;
+      continue;
+    }
+
+    const runStart = hourIndex;
+    while (hourIndex < DAY_HOUR_COUNT && !occupiedHours[hourIndex]) hourIndex += 1;
+    const runEnd = hourIndex - 1;
+    if (runEnd - runStart + 1 >= 3) {
+      rows.push({ type: "hour", hourIndex: runStart });
+      rows.push({ type: "hidden", startHour: runStart + 1, endHour: runEnd - 1 });
+      rows.push({ type: "hour", hourIndex: runEnd });
+    } else {
+      for (let visibleHour = runStart; visibleHour <= runEnd; visibleHour += 1) rows.push({ type: "hour", hourIndex: visibleHour });
+    }
+  }
+
+  const hourTopPx = {};
+  const hiddenRanges = [];
+  let topPx = 0;
+  rows.forEach((row) => {
+    row.topPx = topPx;
+    if (row.type === "hidden") {
+      hiddenRanges.push(row);
+      topPx += WEEK_HIDDEN_ROW_HEIGHT;
+      return;
+    }
+    hourTopPx[row.hourIndex] = topPx;
+    topPx += WEEK_HOUR_ROW_HEIGHT;
+  });
+
+  return {
+    rows,
+    hourTopPx,
+    hiddenRanges,
+    totalHeightPx: topPx,
+    gridTemplateRows: rows.map((row) => `${row.type === "hidden" ? WEEK_HIDDEN_ROW_HEIGHT : WEEK_HOUR_ROW_HEIGHT}px`).join(" ")
+  };
+}
+
+export function getWeekMinutePosition(layout, minutes) {
+  const boundedMinutes = Math.max(0, Math.min(24 * 60, minutes));
+  const hourIndex = Math.min(DAY_HOUR_COUNT - 1, Math.floor(boundedMinutes / 60));
+  const visibleHourTop = layout.hourTopPx[hourIndex];
+  if (visibleHourTop !== undefined) {
+    return visibleHourTop + ((boundedMinutes - hourIndex * 60) / 60) * WEEK_HOUR_ROW_HEIGHT;
+  }
+
+  const hiddenRange = layout.hiddenRanges.find((range) => hourIndex >= range.startHour && hourIndex <= range.endHour);
+  if (hiddenRange) {
+    const rangeStartMinutes = hiddenRange.startHour * 60;
+    const rangeMinutes = (hiddenRange.endHour - hiddenRange.startHour + 1) * 60;
+    return hiddenRange.topPx + ((boundedMinutes - rangeStartMinutes) / rangeMinutes) * WEEK_HIDDEN_ROW_HEIGHT;
+  }
+
+  return layout.totalHeightPx;
+}
+
+export function getMonthOccurrenceSegments(days, occurrences) {
+  const laneUsage = days.map(() => [false, false, false]);
+  const segments = occurrences.flatMap((occurrence) => {
+    const coveredIndexes = days
+      .map((day, index) => {
+        const dayStart = day.date.getTime();
+        const dayEnd = addDays(day.date, 1).getTime();
+        const occurrenceEnd = Math.max(occurrence.endMs, occurrence.startMs + WEEK_SLOT_MINUTES * 60000);
+        return day.inMonth && occurrence.startMs < dayEnd && occurrenceEnd > dayStart ? index : -1;
+      })
+      .filter((index) => index >= 0);
+    if (!coveredIndexes.length) return [];
+
+    const lane = [0, 1, 2].find((candidate) => coveredIndexes.every((index) => !laneUsage[index][candidate])) ?? 2;
+    coveredIndexes.forEach((index) => {
+      laneUsage[index][lane] = true;
+    });
+
+    const segments = [];
+    let segmentStart = coveredIndexes[0];
+    let previous = coveredIndexes[0];
+    coveredIndexes.slice(1).forEach((index) => {
+      const sameWeekRow = Math.floor(index / WEEKDAY_LABELS.length) === Math.floor(previous / WEEKDAY_LABELS.length);
+      if (index === previous + 1 && sameWeekRow) {
+        previous = index;
+        return;
+      }
+      segments.push({ occurrence, lane, startIndex: segmentStart, endIndex: previous });
+      segmentStart = index;
+      previous = index;
+    });
+    segments.push({ occurrence, lane, startIndex: segmentStart, endIndex: previous });
+    return segments;
+  });
+  return segments.map((segment) => {
+    const laneCount = Math.max(1, ...segments
+      .filter((item) => item.startIndex <= segment.endIndex && item.endIndex >= segment.startIndex)
+      .map((item) => item.lane + 1));
+    return { ...segment, laneCount };
+  });
+}
diff --git a/website/src/features/toolboxes/modules/index.jsx b/website/src/features/toolboxes/modules/index.jsx
index 82bd3b0..ff51814 100644
--- a/website/src/features/toolboxes/modules/index.jsx
+++ b/website/src/features/toolboxes/modules/index.jsx
@@ -1,5 +1,5 @@
 // Rôle : registre des outils toolbox, rendu commun et contrôles d'ajout/réorganisation.
-import { useEffect, useMemo, useState } from "react";
+import { lazy, Suspense, useEffect, useMemo, useState } from "react";
 import { createPortal } from "react-dom";
 import { CompactDropdown } from "../../../components/CompactDropdown.jsx";
 import { Icon } from "../../../components/Icon.jsx";
@@ -9,13 +9,9 @@ import { lockBodyScroll } from "../../../utils/bodyScrollLock.js";
 import { TOOLBOX_MODULE_DEFINITIONS, TOOLBOX_MODULES } from "../toolboxModuleRegistry.js";
 import { supportsTextExchange } from "./textImport.js";
 import { CalculatorModule } from "./CalculatorModule.jsx";
-import { CalendarModule } from "./CalendarModule.jsx";
 import { ChecklistModule } from "./ChecklistModule.jsx";
-import { CombosModule } from "./CombosModule.jsx";
 import { CountersModule } from "./CountersModule.jsx";
 import { ImageAnnotationModule } from "./ImageAnnotationModule.jsx";
-import { EquipmentPlannerModule } from "./EquipmentPlannerModule.jsx";
-import { GoalTreeModule } from "./GoalTreeModule.jsx";
 import { LinksModule } from "./LinksModule.jsx";
 import { NotepadModule } from "./NotepadModule.jsx";
 import { ImagesModule } from "./ImagesModule.jsx";
@@ -23,6 +19,11 @@ import { TableModule } from "./TableModule.jsx";
 import { TaskPlannerModule } from "./TaskPlannerModule.jsx";
 import { TimerModule } from "./TimerModule.jsx";
 
+const CombosModule = lazy(() => import("./CombosModule.jsx").then((module) => ({ default: module.CombosModule })));
+const CalendarModule = lazy(() => import("./CalendarModule.jsx").then((module) => ({ default: module.CalendarModule })));
+const GoalTreeModule = lazy(() => import("./GoalTreeModule.jsx").then((module) => ({ default: module.GoalTreeModule })));
+const EquipmentPlannerModule = lazy(() => import("./EquipmentPlannerModule.jsx").then((module) => ({ default: module.EquipmentPlannerModule })));
+
 const MODULE_COMPONENTS = {
   notepad: { ...TOOLBOX_MODULE_DEFINITIONS.notepad, Component: NotepadModule },
   checklist: { ...TOOLBOX_MODULE_DEFINITIONS.checklist, Component: ChecklistModule },
@@ -40,6 +41,8 @@ const MODULE_COMPONENTS = {
   imageAnnotation: { ...TOOLBOX_MODULE_DEFINITIONS.imageAnnotation, Component: ImageAnnotationModule }
 };
 
+const LAZY_MODULE_TYPES = new Set(["combos", "calendar", "goalTree", "equipmentPlanner"]);
+
 const MODULE_COLUMN_IDS = ["left", "right"];
 
 export { TOOLBOX_MODULES };
@@ -300,6 +303,18 @@ function ModuleShell({ toolbox, module, context, reorder, itemGroup = "", onRena
     reorder.getDropPlacement("item", module.id) === "after" ? "drop-after" : "",
     scrollable ? "is-scrollable" : ""
   ].filter(Boolean).join(" ");
+  const componentProps = {
+    toolboxId: toolbox.id,
+    moduleId: module.id,
+    context,
+    editing,
+    setEditing,
+    openEditor: () => {
+      setTextExchangeOpen(false);
+      setEditing(true);
+    },
+    textExchangeOpen
+  };
 
   return (
     <article
@@ -380,23 +395,22 @@ function ModuleShell({ toolbox, module, context, reorder, itemGroup = "", onRena
         </div>
       </header>
       <div className={`module-content ${scrollable ? "is-scrollable legacy-scrollbar" : ""}`}>
-        <Component
-          toolboxId={toolbox.id}
-          moduleId={module.id}
-          context={context}
-          editing={editing}
-          setEditing={setEditing}
-          openEditor={() => {
-            setTextExchangeOpen(false);
-            setEditing(true);
-          }}
-          textExchangeOpen={textExchangeOpen}
-        />
+        {LAZY_MODULE_TYPES.has(module.type) ? (
+          <Suspense fallback={<ModuleLoadingFallback label={label} />}>
+            <Component {...componentProps} />
+          </Suspense>
+        ) : (
+          <Component {...componentProps} />
+        )}
       </div>
     </article>
   );
 }
 
+function ModuleLoadingFallback({ label }) {
+  return <div className="module-loading-fallback">Chargement de {label}...</div>;
+}
+
 function EditableModuleTitle({ value, fallback, onSave, tutorialTarget = "" }) {
   const inlineEdit = useInlineEdit({
     value,
diff --git a/website/src/features/toolboxes/useToolboxActions.js b/website/src/features/toolboxes/useToolboxActions.js
index f360f04..23fa887 100644
--- a/website/src/features/toolboxes/useToolboxActions.js
+++ b/website/src/features/toolboxes/useToolboxActions.js
@@ -87,13 +87,17 @@ export function useToolboxActions({ store, notify, creationTemplate, setConfirmM
     const imageFiles = [...files].filter((file) => file?.type?.startsWith("image/"));
     if (!imageFiles.length) return false;
     const data = store.getModuleData(toolboxId, moduleId, { images: [] });
+    const images = [];
     for (const file of imageFiles) {
       const image = { id: uid("image"), dataUrl: await compressImage(file) };
       const label = labelFromFileName(file.name);
       if (label) image.label = label;
-      data.images.unshift(image);
+      images.unshift(image);
     }
-    return store.updateModuleData(toolboxId, moduleId, data);
+    return store.updateModuleData(toolboxId, moduleId, {
+      ...data,
+      images: [...images, ...(Array.isArray(data.images) ? data.images : [])]
+    });
   }
 
   function createChecklistFromList(gameId, list) {
diff --git a/website/src/styles/toolboxes/_module-shell.scss b/website/src/styles/toolboxes/_module-shell.scss
index c34b484..bdb219c 100644
--- a/website/src/styles/toolboxes/_module-shell.scss
+++ b/website/src/styles/toolboxes/_module-shell.scss
@@ -25,6 +25,15 @@
   min-width: 0;
 }
 
+.module-loading-fallback {
+  padding: var(--space-4);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-md);
+  background: rgba(7, 10, 24, 0.32);
+  color: var(--color-text-secondary);
+  font-size: 14px;
+}
+
 .module-content.is-scrollable {
   max-height: 450px;
   overflow-y: auto;