diff --git a/src/geo/polygon.js b/src/geo/polygon.js
index c8414b63..dbfe2d9d 100644
--- a/src/geo/polygon.js
+++ b/src/geo/polygon.js
@@ -1730,42 +1730,27 @@
         return null;
     }
 
-    function leftmost(p1, p2) {
-        if (!p1) {
-            return p2;
-        }
-        if (p1.x <= p2.x) {
-            if (p1.x < p2.x || (p1.x === p2.x && p1.y < p2.y)) {
-                return p2;
-            }
-        }
-        return p1;
-    }
-
-    // return top-most, left-post point
-    PRO.leftmost = function() {
-        let tl = undefined;
-        for (let p of this.points) {
-            tl = leftmost(tl, p);
-        }
-        return tl;
-    };
-
     PRO.areaDiff = function(poly) {
         let a1 = this.area(),
             a2 = poly.area();
         return (a1 > a2) ? a2 / a1 : a1 / a2;
     };
 
-    PRO.areaOrLength = function(poly) {
-        return this.length === poly.length || this.areaDiff(poly) > 0.98;
+    PRO.unionMatch = function(polys) {
+        return polys.filter(poly => poly.isEquivalent(this)).length;
+        // for (let poly of polys) {
+        //     if (this.isEquivalent(poly)) {
+        //         return true;
+        //     }
+        // }
+        // return false;
     };
 
     /**
      * return logical OR of two polygons' enclosed areas
      *
      * @param {Polygon} poly
-     * @returns {?Polygon} intersected polygon or null if no intersection
+     * @returns {?Polygon} intersected polygon, null if no intersection, or all when indicated
      */
     PRO.union = function(poly, min, all) {
         if (!this.overlaps(poly)) return null;
@@ -1788,33 +1773,10 @@
             let union = POLY().fromClipperTreeUnion(ctre, poly.getZ(), minarea);
             if (all) {
                 if (union.length === 2) {
-                    let src = [ this.leftmost(), poly.leftmost() ];
-                    let dst = [ union[0].leftmost(), union[1].leftmost() ];
-
-                    if (leftmost(src[0], src[1]) === src[1]) {
-                        src.reverse();
-                    }
-                    if (leftmost(dst[0], dst[1]) === dst[1]) {
-                        dst.reverse();
-                    }
-                    if (
-                        src[0].poly && src[1].poly && // missing for cam tabs
-                        src[0].isEqual2D(dst[0]) &&
-                        src[1].isEqual2D(dst[1]) &&
-                        src[0].poly.areaOrLength(dst[0].poly) &&
-                        src[1].poly.areaOrLength(dst[1].poly)
-                    ) {
-                        return null;
-                    // } else {
-                    //     console.log("union debug", {
-                    //         src,
-                    //         dst,
-                    //         d0: src[0].poly.areaDiff(dst[0].poly),
-                    //         d1: src[1].poly.areaDiff(dst[1].poly),
-                    //         m0: src[0].isEqual2D(dst[0]),
-                    //         m1: src[1].isEqual2D(dst[1])
-                    //     });
-                    }
+                    return null;
+                    // if (this.unionMatch(union) || poly.unionMatch(union)) {
+                    //     return null;
+                    // }
                 }
                 return union;
             }
diff --git a/src/kiri/main.js b/src/kiri/main.js
index a955d4f9..910c8d96 100644
--- a/src/kiri/main.js
+++ b/src/kiri/main.js
@@ -1954,9 +1954,9 @@
                         name = name.substring(sp + 1);
                     }
                     UI.mesh.name.innerText = name;
-                    UI.mesh.points.innerText = sel.meta.vertices;
-                    UI.mesh.faces.innerText = sel.meta.vertices / 3;
                 }
+                UI.mesh.points.innerText = sel.meta.vertices;
+                UI.mesh.faces.innerText = sel.meta.vertices / 3;
             } else {
                 UI.mesh.name.innerText = `[${selcount}]`;
                 UI.mesh.points.innerText = '-';
diff --git a/src/mode/fdm/slice.js b/src/mode/fdm/slice.js
index 2b15a665..97d8c017 100644
--- a/src/mode/fdm/slice.js
+++ b/src/mode/fdm/slice.js
@@ -1664,14 +1664,19 @@
         }
         let groups = coplane.group(true);
         // console.log({v3cache, coplane, groups});
+        // let ptotl = Object.values(groups).flat().flat().length;
+        // console.log({ptotl});
+        // let pdone = 0;
         for (let group of Object.values(groups)) {
             for (let polys of group) {
                 for (let poly of polys) {
                     if (poly.area() >= process.sliceSupportArea)
                     tP(poly, polys.face);
+                    // console.log(++pdone / ptotl);
                 }
             }
         }
+
         widget.supports = add;
         return add.length > 0;
     };
@@ -1742,7 +1747,8 @@
                                 .add(arr[1].x, arr[1].y, arr[1].z)
                                 .add(arr[2].x, arr[2].y, arr[2].z);
                         });
-                        let union = POLY.union(parr, 0, true, {wasm:true});
+                        let union = parr.length === 1 ? parr :
+                            POLY.union(parr, 0, true, {wasm:false});
                         union.merged = parr.length;
                         union.face = group[0];
                         return union;
diff --git a/web/kiri/lang/en.js b/web/kiri/lang/en.js
index 6097b76f..9034d35b 100644
--- a/web/kiri/lang/en.js
+++ b/web/kiri/lang/en.js
@@ -381,7 +381,7 @@ kiri.lang['en-us'] = {
     sp_dens_s:      "density",
     sp_dens_l:      ["fraction 0.0 - 1.0","recommended 0.15","0 to disable"],
     sp_size_s:      "pillar size",
-    sp_size_l:      ["pillar width","in millimeters"],
+    sp_size_l:      ["pillar width in millimeters","smaller values exponentially","increase detection times"],
     sp_offs_s:      "part offset",
     sp_offs_l:      ["offset from part","in millimeters"],
     sp_gaps_s:      "gap layers",
@@ -389,9 +389,9 @@ kiri.lang['en-us'] = {
     sp_span_s:      "max span",
     sp_span_l:      ["unsupported span that causes","a new support to be generated","in millimeters"],
     sp_angl_s:      "max angle",
-    sp_angl_l:      ["max overhang angle before","supporting pillar is generated"],
+    sp_angl_l:      ["max overhang angle before","supporting pillar is generated","normal values 45-60","belt values 0-10"],
     sp_area_s:      "min area",
-    sp_area_l:      ["minimum area for","a support column","in millimeters"],
+    sp_area_l:      ["minimum area for","a support column","in millimeters","smaller values will","slow detection"],
     sp_xpnd_s:      "expand",
     sp_xpnd_l:      ["expand support area","beyond part boundary","in millimeters"],
     sp_nozl_s:      "extruder",