Results drop-down box is not properly displayed in document Delete view

STEPS TO REPRODUCE

1. Go to a page which has children (e.g. Sandbox.WebHome or Main.WebHome)
2. Click 'More Actions' > 'Delete'
3. Expand the 'Affect children' box
4. Observe the placement of the Results number drop-down at the top of the Livetable

EXPECTED RESULTS

The drop-down is correctly sized and displayed in the line with the text, see screenshot.

ACTUAL RESULTS

The drop-down is displayed below the text and is elongated to the entire width of the page content, see screenshot.

The issue seems to be reproducing in page Delete view starting XWiki 14.4.2 (reproduced also on 14.10.1 and 14.4.7), but it could not be reproduced on XWiki 14.4.1.