The url bar has no border outline, and no visible difference in background colour from the browser UI.
However there is a graphical glitch in the corners of the URL bar, which makes me wonder if the outline is so superfine that it doesn't show on non-retina screens, but that the antialiasing of the corners, being slightly thicker does show.
Safari on this version of macOS does have a border for the URL bar, and it looks better. Alternative options might be an internal shadow to create a setback depth, or a darker background, but honestly, the outline is the clearest way to demarcate the extents of the text entry field.
Version 1.0.6 (145), WebKit 619.1.11.111.2
Ventura (13)
