diff --git a/src/gui/fontzlib.cpp b/src/gui/fontzlib.cpp
index c5f5fcf05..e2b9bcc48 100644
--- a/src/gui/fontzlib.cpp
+++ b/src/gui/fontzlib.cpp
@@ -38,9 +38,21 @@ struct InflateBlock {
 };
 
 ImFont* FurnaceGUI::addFontZlib(const void* data, size_t len, float size_pixels, const ImFontConfig* font_cfg, const ImWchar* glyph_ranges) {
+  // find font in cache
+  logV("addFontZlib...");
+  for (FurnaceGUIUncompFont& i: fontCache) {
+    if (i.origPtr==data && i.origLen==len) {
+      logV("found in cache");
+      ImFontConfig fontConfig=(font_cfg==NULL)?ImFontConfig():(*font_cfg);
+      fontConfig.FontDataOwnedByAtlas=false;
+
+      return ImGui::GetIO().Fonts->AddFontFromMemoryTTF(i.data,i.len,size_pixels,&fontConfig,glyph_ranges);
+    }
+  }
+
   z_stream zl;
   memset(&zl,0,sizeof(z_stream));
-  logV("addFontZlib...");
+  logV("not found in cache - decompressing...");
 
   zl.avail_in=len;
   zl.next_in=(Bytef*)data;
@@ -116,10 +128,11 @@ ImFont* FurnaceGUI::addFontZlib(const void* data, size_t len, float size_pixels,
     delete i;
   }
   blocks.clear();
-  len=finalSize;
+
+  fontCache.push_back(FurnaceGUIUncompFont(data,len,finalData,finalSize));
 
   ImFontConfig fontConfig=(font_cfg==NULL)?ImFontConfig():(*font_cfg);
-  fontConfig.FontDataOwnedByAtlas=true;
+  fontConfig.FontDataOwnedByAtlas=false;
 
   return ImGui::GetIO().Fonts->AddFontFromMemoryTTF(finalData,finalSize,size_pixels,&fontConfig,glyph_ranges);
 }
diff --git a/src/gui/gui.h b/src/gui/gui.h
index 9473fa5bd..a037090cb 100644
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@@ -1546,6 +1546,18 @@ struct FurnaceGUIPerfMetric {
     elapsed(0) {}
 };
 
+struct FurnaceGUIUncompFont {
+  const void* origPtr;
+  size_t origLen;
+  void* data;
+  size_t len;
+  FurnaceGUIUncompFont(const void* ptr, size_t len, void* d, size_t l):
+    origPtr(ptr),
+    origLen(len),
+    data(d),
+    len(l) {}
+};
+
 struct FurnaceGUIBackupEntry {
   String name;
   uint64_t size;
@@ -1778,6 +1790,7 @@ class FurnaceGUI {
   MIDIMap midiMap;
   int learning;
 
+  std::vector<FurnaceGUIUncompFont> fontCache;
   ImFont* mainFont;
   ImFont* iconFont;
   ImFont* furIconFont;