The ornamental design for a portableseat, as shown and described.
FIG. 1 is a front elevation view of a portable chair showing my new design as attached to a support in the form of a tree;
FIG. 2 is a front side perspective view, the opposite side being a mirror image thereof;
FIG. 3 is a rear side perspective view;
FIG. 4 is a top view thereof;
FIG. 5 is a top view of the seat portion thereof, shown prior to attachment to a tree or other support at one end of the seat portion and prior to attachment to the support members thereof at the opposite end of the seat portion;
FIG. 6 is a side view of the support members of the portable seat, unattached to the seat, in a closed position shown with rectangular portions attached to the inner surfaces in alternate positions than what is shown in FIG. 4;
FIG. 7 is an enlarged end view of the support members of FIG. 6;
FIG. 8 is an enlarged end view of the support members of FIG. 6 but showing the end of the support members in an open position for supporting the seat as depicted in FIGS. 1-3;
FIG. 9 is a perpendicular enlarged end view of the support members of FIG. 7; and,
FIG. 10 is an end view of the support members of FIG. 6 of the chair.
The broken lines in the figures illustrate environment and form no part of the claimed design.