Check for right sense of bigger flag.

tty.c

@@ -871,7 +871,7 @@ tty_is_visible(const struct tty_ctx *ctx, u_int px, u_int py, u_int nx,
 	struct window_pane	*wp = ctx->wp;
 	u_int			 xoff = wp->xoff + px, yoff = wp->yoff + py;
 
-	if (ctx->bigger)
+	if (!ctx->bigger)
 		return (1);
 	if (xoff + nx <= ctx->ox || xoff >= ctx->ox + ctx->sx ||
 	    yoff + ny <= ctx->oy || yoff >= ctx->oy + ctx->sy) {