Portable chair

<figref idref="DRAWINGS">FIG. 1</figref> is a top, front, right perspective view of a portable chair showing our new design;

<figref idref="DRAWINGS">FIG. 2</figref> is a front view thereof;

<figref idref="DRAWINGS">FIG. 3</figref> is a rear view thereof;

<figref idref="DRAWINGS">FIG. 4</figref> is a left side view thereof;

<figref idref="DRAWINGS">FIG. 5</figref> is a right side view thereof;

<figref idref="DRAWINGS">FIG. 6</figref> is a top view thereof; and,

<figref idref="DRAWINGS">FIG. 7</figref> is a bottom view thereof.

The broken lines immediately adjacent to the shaded area represent unclaimed boundaries of the design. The broken lines showing the remainder of the portable chair represent unclaimed subject matter and form no part of the claimed design.