diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 77b80b94..785d2aee 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -15,9 +15,6 @@ updates:
         versions: [">=1.4"]
       - dependency-name: "alembic"
         versions: [">=1.11"]
-      # cachetools 6 removed cachetools.func.mru_cache, still used by modules/zim.
-      - dependency-name: "cachetools"
-        update-types: ["version-update:semver-major"]
     groups:
       python-dependencies:
         patterns:
diff --git a/app/src/reportWebVitals.js b/app/src/reportWebVitals.js
index 14ba227b..e3768eef 100644
--- a/app/src/reportWebVitals.js
+++ b/app/src/reportWebVitals.js
@@ -1,11 +1,12 @@
 const reportWebVitals = onPerfEntry => {
-    if (onPerfEntry && onPerfEntry instanceof Function) {
-        import('web-vitals').then(({getCLS, getFID, getFCP, getLCP, getTTFB}) => {
-            getCLS(onPerfEntry);
-            getFID(onPerfEntry);
-            getFCP(onPerfEntry);
-            getLCP(onPerfEntry);
-            getTTFB(onPerfEntry);
+    if (typeof onPerfEntry === 'function') {
+        // web-vitals 3+ renamed get* to on*; 5+ replaced FID with INP.
+        return import('web-vitals').then(({onCLS, onINP, onFCP, onLCP, onTTFB}) => {
+            onCLS(onPerfEntry);
+            onINP(onPerfEntry);
+            onFCP(onPerfEntry);
+            onLCP(onPerfEntry);
+            onTTFB(onPerfEntry);
         });
     }
 };
diff --git a/app/src/reportWebVitals.test.js b/app/src/reportWebVitals.test.js
new file mode 100644
index 00000000..31d24251
--- /dev/null
+++ b/app/src/reportWebVitals.test.js
@@ -0,0 +1,28 @@
+jest.mock('web-vitals', () => ({
+    onCLS: jest.fn(),
+    onINP: jest.fn(),
+    onFCP: jest.fn(),
+    onLCP: jest.fn(),
+    onTTFB: jest.fn(),
+}));
+
+import reportWebVitals from './reportWebVitals';
+import * as webVitals from 'web-vitals';
+
+describe('reportWebVitals', () => {
+    test('subscribes the callback to every current web-vitals metric', async () => {
+        const callback = jest.fn();
+        const pending = reportWebVitals(callback);
+        expect(pending).toBeDefined();
+        await pending;
+        for (const name of ['onCLS', 'onINP', 'onFCP', 'onLCP', 'onTTFB']) {
+            expect(webVitals[name]).toHaveBeenCalledWith(callback);
+        }
+    });
+
+    test('does nothing without a function', async () => {
+        jest.clearAllMocks();
+        expect(reportWebVitals(undefined)).toBeUndefined();
+        expect(webVitals.onCLS).not.toHaveBeenCalled();
+    });
+});
diff --git a/modules/zim/lib.py b/modules/zim/lib.py
index 95761df2..667d5359 100644
--- a/modules/zim/lib.py
+++ b/modules/zim/lib.py
@@ -260,7 +260,7 @@ def search_all_zims(session: Session, search_str: str, tag_names: List[str] = No
     return all_results
 
 
-@cachetools.func.mru_cache(maxsize=1_000)
+@cachetools.func.lru_cache(maxsize=1_000)
 def get_estimates(search_str: str) -> List[int]:
     zims = Zims.get_all()
     estimates = [i.estimate(search_str) for i in zims]
diff --git a/modules/zim/test/test_lib.py b/modules/zim/test/test_lib.py
index b11532d1..c6b987dc 100644
--- a/modules/zim/test/test_lib.py
+++ b/modules/zim/test/test_lib.py
@@ -411,3 +411,15 @@ def test_get_custom_zims_directory(async_client, test_directory, test_wrolpi_con
     get_wrolpi_config().zims_destination = 'custom/zims'
 
     assert lib.get_zim_directory() == (test_directory / 'custom/zims')
+
+
+def test_get_estimates_is_cached():
+    """Repeated estimates for the same search string do not re-query the Zims."""
+    from unittest import mock
+    from modules.zim import lib
+
+    lib.get_estimates.cache_clear()
+    with mock.patch.object(lib.Zims, 'get_all', return_value=[]) as get_all:
+        assert lib.get_estimates('cached search') == []
+        assert lib.get_estimates('cached search') == []
+    assert get_all.call_count == 1
diff --git a/requirements.txt b/requirements.txt
index eb150470..f7b838b4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@ SQLAlchemy[asyncio]==1.3.24
 aiohttp==3.14.3
 alembic==1.10.4
 beautifulsoup4==4.15.0
-cachetools==5.5.2
+cachetools==7.2.0
 cryptography==50.0.2
 ebooklib==0.20
 feedparser==6.0.14