chromium/third_party/blink/web_tests/css3/filters/backdrop-filter-transform.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>backdrop-filter: backdrop-filter plus transform should be applied correctly</title>

<!--Expected: A green box with an overlapping rotated box that inverts content behind it. -->

<div class="colorbox"></div>
<div class="filterbox"></div>

<!-- TODO(978481): Convert this back to WPT test. See crbug.com/978481 for
  an implementation in WPT that is waiting for the WPT Fuzzy Matching feature.
-->

<style>
div {
    position: absolute;
    width: 100px;
    height: 100px;
    left: 100px;
    top: 100px;
}
.colorbox {
    background: green;
}
.filterbox {
    top: 140px;
    backdrop-filter: invert(1);
    transform: rotate(30deg);
    border-radius: 10px;
}
</style>