Bug 193656 – [css-grid] abspos inside grid can have negative sizes

• Component: CSS
• Status: RESOLVED CONFIGURATION CHANGED

[Oriol Brufau]

Created attachment 359700 [details]
testcase

Run this code: https://jsfiddle.net/9mjg2fxt/

```css
#grid {
  display: grid;
  grid: 100px / 100px;
  border: solid;
  width: 100px;
  height: 100px;
  position: relative;
}
#abspos {
  position: absolute;
  left: 30px;
  right: 40px;
  grid-column-end: 1;
  color: cyan;
  border: 10px solid blue;
}
```
```html
<div id="log"></div>
<div id="grid">
  <div>
    <div id="abspos"></div>
  </div>
</div>
```
```js
let w = document.getElementById('abspos').offsetWidth;
document.getElementById("log").textContent = "offsetWidth = " + w;
```

Result: the offsetWidth is -70, and no blue border is shown
Expected: It should be 20 instead. And the blue border should be visible.

Chromium and Firefox do it correctly.

[Ahmad Saleem]

I am unable to reproduce the bug using attached test case in attachment field using Safari 15.6 on macOS 12.5 and it shows "offset of 20 px" similar to other browsers (Chrome Canary 106 and Firefox Nightly 105). I am marking this as "RESOLVED CONFIGURATION CHANGED". Thanks!