diff --git a/index.html b/index.html
index 33e4ba6..b08036b 100644
--- a/index.html
+++ b/index.html
@@ -2,8 +2,12 @@
 <html lang="en">
   <head>
     <meta charset="UTF-8" />
-    <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
-    <link rel="apple-touch-icon" href="/apple-touch-icon.png" />
+    <!-- favicon.ico for Safari before 26 (no SVG favicons), the SVG for the
+         others. "?v=2": a new address, so browsers fetch the icons afresh
+         instead of a cached older one - raise it when the logo changes. -->
+    <link rel="icon" href="/favicon.ico?v=2" sizes="32x32" />
+    <link rel="icon" href="/favicon.svg?v=2" type="image/svg+xml" />
+    <link rel="apple-touch-icon" href="/apple-touch-icon.png?v=2" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>glpython</title>
     <script src="/coi-serviceworker.js"></script>
diff --git a/public/favicon.ico b/public/favicon.ico
new file mode 100644
index 0000000..63259f0
Binary files /dev/null and b/public/favicon.ico differ
diff --git a/scripts/check-ide-browser.mjs b/scripts/check-ide-browser.mjs
index a4b4f2d..da4d75f 100644
--- a/scripts/check-ide-browser.mjs
+++ b/scripts/check-ide-browser.mjs
@@ -596,6 +596,24 @@ try {
     await context.close()
   })
 
+  await check('icons: favicon.ico, favicon.svg, apple-touch-icon, each ?v=2 (P41)', async () => {
+    const context = await newContext()
+    const page = await open(context, base)
+    assert.deepEqual(await page.evaluate(() => [...document.querySelectorAll('link[rel~="icon"], link[rel="apple-touch-icon"]')].map((link) => [link.rel, link.getAttribute('href'), link.type, link.getAttribute('sizes')])), [
+      ['icon', '/favicon.ico?v=2', '', '32x32'],
+      ['icon', '/favicon.svg?v=2', 'image/svg+xml', null],
+      ['apple-touch-icon', '/apple-touch-icon.png?v=2', '', null],
+    ])
+    // Through the page, i.e. through the service worker: served, with the query, as images.
+    const served = await page.evaluate(async () => Promise.all(['/favicon.ico?v=2', '/favicon.svg?v=2', '/apple-touch-icon.png?v=2'].map(async (path) => {
+      const response = await fetch(path)
+      return [path, response.status, response.headers.get('content-type')?.split(';')[0], (await response.arrayBuffer()).byteLength > 0]
+    })))
+    assert.deepEqual(served.map(([path, status, , filled]) => [path, status, filled]), [['/favicon.ico?v=2', 200, true], ['/favicon.svg?v=2', 200, true], ['/apple-touch-icon.png?v=2', 200, true]])
+    assert.ok(served.every(([, , type]) => /^image\//.test(type)), `as images: ${served.map(([, , type]) => type).join(', ')}`)
+    await context.close()
+  })
+
   await check('⋮ «Info»: the version from version.json, and the update check', async () => {
     const { version } = JSON.parse(readFileSync(new URL('../dist/version.json', import.meta.url), 'utf8'))
     const context = await newContext()