diff --git a/commafeed-tweaks.js b/commafeed-tweaks.js
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+++ b/commafeed-tweaks.js
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+/**
+ * commafeed-tweaks.js
+ *
+ * Client-side behavior tweaks for CommaFeed (Athou/commafeed), applied from
+ * outside the app bundle.
+ *
+ * Install (either):
+ *   1. Paste this file's contents into Settings -> Custom code -> Custom JS.
+ *      CommaFeed serves it as `custom_js.js` and loads it after the app starts.
+ *   2. Serve this file alongside the app and add
+ *        <script src="commafeed-tweaks.js"></script>
+ *      to index.html.
+ *
+ * All listeners attach to `window`, so load timing relative to React doesn't matter.
+ */
+(function () {
+    'use strict'
+
+    if (window.__commafeedTweaksInstalled) return
+    window.__commafeedTweaksInstalled = true
+
+    const log = (...args) => console.debug('[commafeed-tweaks]', ...args)
+
+    /**
+     * Disable swipe-right-to-open the mobile sidebar.
+     *
+     * Upstream (pages/app/Layout.tsx) wraps the AppShell in a react-swipeable Box
+     * whose touch listeners live on that element and open the menu on a rightward
+     * swipe. We catch touchmove on window in the capture phase and stop propagation
+     * of rightward-horizontal moves so they never reach that element. No
+     * preventDefault, so native scrolling is untouched; leftward swipes still pass
+     * through, so swipe-left-to-close keeps working.
+     */
+    function disableSwipeToOpenMenu() {
+        let startX = 0
+        let startY = 0
+
+        window.addEventListener('touchstart', e => {
+            const t = e.touches[0]
+            if (!t) return
+            startX = t.clientX
+            startY = t.clientY
+        }, { capture: true, passive: true })
+
+        window.addEventListener('touchmove', e => {
+            const t = e.touches[0]
+            if (!t) return
+            const dx = t.clientX - startX
+            const dy = t.clientY - startY
+            if (dx > 0 && Math.abs(dx) > Math.abs(dy)) {
+                e.stopPropagation()
+            }
+        }, { capture: true, passive: true })
+
+        log('swipe-to-open menu disabled')
+    }
+
+    disableSwipeToOpenMenu()
+})()