chromium/third_party/blink/web_tests/editing/selection/5136696.html

<script>
if (window.testRunner) {
    testRunner.dumpAsText();
    testRunner.waitUntilDone();
}

function verifyResults(inputElement, selectedText) {
    if (document.activeElement != inputElement) {
        document.body.innerHTML = "FAIL (text field was not selected)";
        return;
    }

    if (frames[0].getSelection().toString() != selectedText) {
        document.body.innerHTML = "FAIL (unexpected selection)";
        return;
    }

    document.body.innerHTML = "PASS";
}
    
function runTest() {
    var textToSelect = "This text should be selected, but this frame shouldn't be focused.";
    frame = frames[0];
    frame.focus();
    s = frame.getSelection();
    s.collapse(frame.document.body, 0);
    frame.document.execCommand("InsertText", false, textToSelect);
    frame.document.execCommand("SelectAll");

    var inputElement = document.getElementById("input");
    inputElement.focus();

    verifyResults(inputElement, textToSelect);

    if (window.testRunner)
        testRunner.notifyDone();
}
</script>
<p>This tests to make sure that a selection in one frame isn't cleared when focusing a node in a different frame.</p>
<iframe border="1" src="../resources/contenteditable-iframe-src.html" onload="runTest();"></iframe><br>
<input type="text" id="input" value="This text field should be focused." size="30">