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diff --git a/dom/base/test/test_focus_scrollable_input.html b/dom/base/test/test_focus_scrollable_input.html
new file mode 100644
index 0000000000..ca48f3a263
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+++ b/dom/base/test/test_focus_scrollable_input.html
@@ -0,0 +1,56 @@
+<!doctype html>
+<title>Test for bug 1617342</title>
+<script src="/tests/SimpleTest/SimpleTest.js"></script>
+<script src="/tests/SimpleTest/EventUtils.js"></script>
+<style>
+  input {
+    /* Make them small enough that any value overflows */
+    height: 10px;
+    width: 10px;
+    box-sizing: border-box;
+    font: 16px/1 monospace;
+  }
+</style>
+<input type="text" id="start" value="aaaaaaaaaa">
+
+<input type="text" value="aaaaaaaaaa">
+<input type="number" value="1111">
+<input type="search" value="aaaaaaa">
+<input type="url" value="https://fooooooooooo">
+
+<input type="text" id="end" value="aaaaaaaaaa">
+<script>
+  SimpleTest.waitForExplicitFinish();
+  SimpleTest.waitForFocus(async function() {
+    // Enable Full Keyboard Access emulation on Mac.
+    if (navigator.platform.indexOf("Mac") === 0) {
+      await SpecialPowers.pushPrefEnv({"set": [["accessibility.tabfocus", 7]]});
+    }
+
+    const start = document.getElementById("start");
+
+    start.focus();
+
+    const end = document.getElementById("end");
+
+    is(document.activeElement, start, "Focus moved sanely");
+
+    let lastActiveElement = start;
+    let stack = [start];
+
+    do {
+      synthesizeKey("KEY_Tab");
+      isnot(document.activeElement, lastActiveElement, "Focus should've moved once per tab keypress");
+      lastActiveElement = document.activeElement;
+      stack.push(lastActiveElement);
+    } while (document.activeElement != end)
+
+    do {
+      let previous = stack.pop();
+      is(document.activeElement, previous, "Focus should've moved backwards as expected");
+      synthesizeKey("KEY_Tab", {shiftKey: true});
+    } while (stack.length);
+
+    SimpleTest.finish();
+  });
+</script>