The ornamental design for a lightfixture, as shown and described.
FIG. 1 is a first perspective view of a light fixture showing our new design;
FIG. 2 is a second perspective view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a front view thereof; wherein the rear view is a mirror image of FIG. 5; and,
FIG. 6 is a side view thereof wherein the alternate side view is a mirror image of FIG. 6.
The broken lines immediately adjacent to the shaded area represent unclaimed boundaries of the design. The broken lines showing the remainder of the light fixture are for environmental purposes only and form no part of the claimed design.