diff --git a/lua/api/core/gui.lua b/lua/api/core/gui.lua
index c3a12fc..6afdec8 100644
--- a/lua/api/core/gui.lua
+++ b/lua/api/core/gui.lua
@@ -107,10 +107,6 @@ function gui.fillCircle(x, y, radius, color, background) end
 ---@param border? GuiColor Omitted for no border.
 function gui.roundRect(x, y, w, h, radius, background, top, bottom, border) end
 
----Temporarily gives the app the full panel, including firmware chrome.
----@param on boolean
-function gui.setFullscreen(on) end
-
 ---Fills a polygon.
 ---@param xs integer[]
 ---@param ys integer[]
diff --git a/native/include/lua/providers.h b/native/include/lua/providers.h
index ab5328b..e450c08 100644
--- a/native/include/lua/providers.h
+++ b/native/include/lua/providers.h
@@ -136,9 +136,6 @@ public:
   virtual void roundRect(int32_t x, int32_t y, int32_t w, int32_t h,
                          int32_t radius, int32_t background, const int32_t* top,
                          const int32_t* bottom, const int32_t* border) = 0;
-  // Hands the app the whole panel, including whatever chrome the firmware
-  // paints.
-  virtual void setFullscreen(bool on) = 0;
   // Applies everything drawn since the last commit. The runtime supplies only
   // the timing -- the end of a callback batch -- because that is the one fact a
   // driver cannot know; which region to touch, which waveform, and whether to
diff --git a/native/src/bindings/core/gui.cpp b/native/src/bindings/core/gui.cpp
index 091fa4d..4c1f296 100644
--- a/native/src/bindings/core/gui.cpp
+++ b/native/src/bindings/core/gui.cpp
@@ -125,12 +125,6 @@ int roundRect(lua_State* state) {
   return 0;
 }
 
-int setFullscreen(lua_State* state) {
-  luaL_checkany(state, 1);
-  provider(state).setFullscreen(lua_toboolean(state, 1) != 0);
-  return 0;
-}
-
 void readIntegers(lua_State* state, int index, std::vector<int32_t>& out) {
   const lua_Integer count = luaL_len(state, index);
   for (lua_Integer at = 1; at <= count; at++) {
@@ -291,9 +285,6 @@ const luaL_Reg FUNCTIONS[] = {
     // without a gradient use top.
     // @param border GuiColor|nil Omitted for no border.
     {"roundRect", roundRect},
-    // ---Temporarily gives the app the full panel, including firmware chrome.
-    // @param on boolean
-    {"setFullscreen", setFullscreen},
     // --- Fills a polygon.
     // @param xs integer[]
     // @param ys integer[]
diff --git a/native/test/fake_providers.h b/native/test/fake_providers.h
index 247f82c..4448fbe 100644
--- a/native/test/fake_providers.h
+++ b/native/test/fake_providers.h
@@ -154,7 +154,6 @@ struct Fs : FsProvider {
 struct Gui : GuiProvider {
   std::string trace;
   int32_t degrees = 0;
-  bool fullscreen = false;
   bool gradient = false;
 
   FontIds fonts() const override {
@@ -195,7 +194,6 @@ struct Gui : GuiProvider {
     trace += border ? ",border" : ",-";
     trace += ");";
   }
-  void setFullscreen(bool on) override { fullscreen = on; }
   // Stands in for an e-ink panel, where a second commit is a second visible
   // refresh.
   void commit() override { commits++; }
diff --git a/native/test/runtime_test.cpp b/native/test/runtime_test.cpp
index 637623d..9cfeb69 100644
--- a/native/test/runtime_test.cpp
+++ b/native/test/runtime_test.cpp
@@ -129,12 +129,10 @@ int main() {
       "'confirm')");
   assert(bench.touch.calibration[3] == 400);
 
-  // Chrome control and gradients are core: an e-ink provider flattens what it
-  // cannot show.
-  run(state, "gui.setFullscreen(true)\n"
-             "gui.roundRect(0, 0, 10, 10, 4, 0, 0xFF, 0x00)\n"
+  // Gradients are core: an e-ink provider flattens what it cannot show.
+  run(state, "gui.roundRect(0, 0, 10, 10, 4, 0, 0xFF, 0x00)\n"
              "gui.roundRect(0, 0, 10, 10, 4, 0, nil, nil, 0xFF)");
-  assert(bench.gui.fullscreen && bench.gui.gradient);
+  assert(bench.gui.gradient);
   assert(bench.gui.trace.find("roundRect(-,border);") != std::string::npos);
 
   bench.gui.trace.clear();