diff --git a/wled00/FX_2Dfcn.cpp b/wled00/FX_2Dfcn.cpp
index ad7f3a10..3ec12a42 100644
--- a/wled00/FX_2Dfcn.cpp
+++ b/wled00/FX_2Dfcn.cpp
@@ -71,6 +71,9 @@ void WS2812FX::setUpMatrix() {
     customMappingTable = new uint16_t[Segment::maxWidth * Segment::maxHeight];
 
     if (customMappingTable != nullptr) {
+      int gapSize = 0;
+      int8_t *gapTable = nullptr;
+
       customMappingSize = Segment::maxWidth * Segment::maxHeight;
 
       // fill with empty in case we don't fill the entire matrix
@@ -78,21 +81,50 @@ void WS2812FX::setUpMatrix() {
         customMappingTable[i] = (uint16_t)-1;
       }
 
+      char fileName[32];
+      strcpy_P(fileName, PSTR("/ledgap.json"));
+      bool isFile = WLED_FS.exists(fileName);
+
+      if (isFile && requestJSONBufferLock(20)) {
+        DEBUG_PRINT(F("Reading LED gap from "));
+        DEBUG_PRINTLN(fileName);
+
+        if (readObjectFromFile(fileName, nullptr, &doc)) {
+          // the array is similar to ledmap, except it has only 3 values:
+          // -1 ... missing pixel (do not increase pixel count)
+          //  0 ... inactive pixel (it does count, but should be mapped out)
+          //  1 ... active pixel
+          JsonArray map = doc.as<JsonArray>();
+          gapSize = map.size();
+          if (!map.isNull() && gapSize >= customMappingSize) {  // not an empty map
+            gapTable = new int8_t[gapSize];
+            for (size_t i = 0; i < gapSize; i++) {
+              gapTable[i] = constrain(map[i], -1, 1);
+            }
+          }
+        }
+        releaseJSONBufferLock();
+      }
+
       uint16_t x, y, pix=0; //pixel
       for (size_t pan = 0; pan < panel.size(); pan++) {
         Panel &p = panel[pan];
         uint16_t h = p.vertical ? p.height : p.width;
         uint16_t v = p.vertical ? p.width  : p.height;
         for (size_t j = 0; j < v; j++){
-          for(size_t i = 0; i < h; i++, pix++) {
+          for(size_t i = 0; i < h; i++) {
             y = (p.vertical?p.rightStart:p.bottomStart) ? v-j-1 : j;
             x = (p.vertical?p.bottomStart:p.rightStart) ? h-i-1 : i;
             x = p.serpentine && j%2 ? h-x-1 : x;
-            customMappingTable[(p.yOffset + (p.vertical?x:y)) * Segment::maxWidth + p.xOffset + (p.vertical?y:x)] = pix;
+            size_t index = (p.yOffset + (p.vertical?x:y)) * Segment::maxWidth + p.xOffset + (p.vertical?y:x);
+            if (!gapTable || (gapTable && gapTable[index] >  0)) customMappingTable[index] = pix;
+            if (!gapTable || (gapTable && gapTable[index] >= 0)) pix++;
           }
         }
       }
 
+      if (gapTable) delete[] gapTable;
+
       #ifdef WLED_DEBUG
       DEBUG_PRINT(F("Matrix ledmap:"));
       for (uint16_t i=0; i<customMappingSize; i++) {
diff --git a/wled00/FX_fcn.cpp b/wled00/FX_fcn.cpp
index 58b17355..6e049ed2 100644
--- a/wled00/FX_fcn.cpp
+++ b/wled00/FX_fcn.cpp
@@ -1014,10 +1014,11 @@ void WS2812FX::finalizeInit(void)
     #endif
   }
 
-  if (!isMatrix) { // if 2D then max values defined in setUpMatrix() using panel set-up
+  if (isMatrix) setUpMatrix();
+  else {
     Segment::maxWidth  = _length;
     Segment::maxHeight = 1;
-   }
+  }
 
   //initialize leds array. TBD: realloc if nr of leds change
   if (Segment::_globalLeds) {
@@ -1583,7 +1584,7 @@ void WS2812FX::loadCustomPalettes() {
 
 //load custom mapping table from JSON file (called from finalizeInit() or deserializeState())
 void WS2812FX::deserializeMap(uint8_t n) {
-  if (isMatrix) return; // 2D support creates its own ledmap
+  //if (isMatrix) return; // 2D support creates its own ledmap
 
   char fileName[32];
   strcpy_P(fileName, PSTR("/ledmap"));
diff --git a/wled00/cfg.cpp b/wled00/cfg.cpp
index a547642e..ff91a674 100644
--- a/wled00/cfg.cpp
+++ b/wled00/cfg.cpp
@@ -130,8 +130,6 @@ bool deserializeConfig(JsonObject doc, bool fromFS) {
       p.options = 0;
       strip.panel.push_back(p);
     }
-
-    strip.setUpMatrix();
   }
   #endif
 
diff --git a/wled00/set.cpp b/wled00/set.cpp
index fa433fae..6c776df2 100644
--- a/wled00/set.cpp
+++ b/wled00/set.cpp
@@ -673,11 +673,11 @@ void handleSettingsSet(AsyncWebServerRequest *request, byte subPage)
         pO[l] = 'H'; p.height      = request->arg(pO).toInt();
         strip.panel.push_back(p);
       }
+      strip.setUpMatrix(); // will check limits
     } else {
       Segment::maxWidth  = strip.getLengthTotal();
       Segment::maxHeight = 1;
     }
-    strip.setUpMatrix(); // will check limits
   }
   #endif