v133 · dom
Focus Matrix
Chrome 133 fixed mouse focus for slotted elements: clicking in the gutter of a custom element now focuses the slotted <input> (flat-tree traversal) instead of the shadow host. This matrix shows every slottable form element and verifies the fix in your browser.
checking Shadow DOM…
checking slot focus behaviour…
Flat-tree focus behaviour matrix
| Element | Slotted into shadow root? | Pre-133 focus target on click | Chrome 133+ focus target | Status |
|---|---|---|---|---|
<input type="text"> |
Yes | Shadow host | Slotted input | fixed |
<input type="checkbox"> |
Yes | Shadow host | Slotted checkbox | fixed |
<select> |
Yes | Shadow host | Slotted select | fixed |
<textarea> |
Yes | Shadow host | Slotted textarea | fixed |
<button> |
Yes | Shadow host | Slotted button | fixed |
<input> (not slotted) |
No (shadow-internal) | Shadow-internal input | Shadow-internal input | unchanged |
Live interactive probes
Click anywhere in each card (the gutter, not just the element). The "Focused element" shows what document.activeElement becomes.
What the fix changed
When a mouse click falls on a non-focusable part of a shadow host (its padding, border, or a non-interactive shadow-internal child), the browser walks up the tree to find a focusable fallback. Pre-133 this used the composed tree order, which could land on the shadow host itself. Chrome 133 traverses the flat tree instead, so it finds the assigned slot and focuses the slotted content — exactly what users and authors expect.