diff --git a/drivers/avr/ssd1306.c b/drivers/avr/ssd1306.c
index 205f749502..1a09a2bcb7 100644
--- a/drivers/avr/ssd1306.c
+++ b/drivers/avr/ssd1306.c
@@ -11,6 +11,8 @@
 #    include "sendchar.h"
 #    include "timer.h"
 
+struct CharacterMatrix display;
+
 // Set this to 1 to help diagnose early startup problems
 // when testing power-on with ble.  Turn it off otherwise,
 // as the latency of printing most of the debug info messes
diff --git a/drivers/avr/ssd1306.h b/drivers/avr/ssd1306.h
index 9669d1b7e7..9131afcf61 100644
--- a/drivers/avr/ssd1306.h
+++ b/drivers/avr/ssd1306.h
@@ -66,7 +66,7 @@ struct CharacterMatrix {
     bool     dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(void);
 void iota_gfx_task(void);
diff --git a/keyboards/claw44/ssd1306.c b/keyboards/claw44/ssd1306.c
index e04a431357..7dea1cc176 100644
--- a/keyboards/claw44/ssd1306.c
+++ b/keyboards/claw44/ssd1306.c
@@ -10,6 +10,8 @@
 #include "sendchar.h"
 #include "timer.h"
 
+struct CharacterMatrix display;
+
 extern const unsigned char font[] PROGMEM;
 
 // Set this to 1 to help diagnose early startup problems
diff --git a/keyboards/claw44/ssd1306.h b/keyboards/claw44/ssd1306.h
index 0ca093093a..11a3cc67f4 100644
--- a/keyboards/claw44/ssd1306.h
+++ b/keyboards/claw44/ssd1306.h
@@ -65,7 +65,7 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(bool rotate);
 void iota_gfx_task(void);
diff --git a/keyboards/comet46/ssd1306.c b/keyboards/comet46/ssd1306.c
index abbed4a49f..4bd2d80bc4 100644
--- a/keyboards/comet46/ssd1306.c
+++ b/keyboards/comet46/ssd1306.c
@@ -10,6 +10,8 @@
 #include "sendchar.h"
 #include "timer.h"
 
+struct CharacterMatrix display;
+
 extern const unsigned char font[] PROGMEM;
 
 // Set this to 1 to help diagnose early startup problems
diff --git a/keyboards/comet46/ssd1306.h b/keyboards/comet46/ssd1306.h
index 0ca093093a..11a3cc67f4 100644
--- a/keyboards/comet46/ssd1306.h
+++ b/keyboards/comet46/ssd1306.h
@@ -65,7 +65,7 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(bool rotate);
 void iota_gfx_task(void);
diff --git a/keyboards/crkbd/ssd1306.c b/keyboards/crkbd/ssd1306.c
index b2676f386f..4ec8a9a00f 100644
--- a/keyboards/crkbd/ssd1306.c
+++ b/keyboards/crkbd/ssd1306.c
@@ -10,6 +10,8 @@
 #include "sendchar.h"
 #include "timer.h"
 
+struct CharacterMatrix display;
+
 extern const unsigned char font[] PROGMEM;
 
 #ifndef OLED_BLANK_CHAR
diff --git a/keyboards/crkbd/ssd1306.h b/keyboards/crkbd/ssd1306.h
index 0ca093093a..11a3cc67f4 100644
--- a/keyboards/crkbd/ssd1306.h
+++ b/keyboards/crkbd/ssd1306.h
@@ -65,7 +65,7 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(bool rotate);
 void iota_gfx_task(void);
diff --git a/keyboards/helix/local_drivers/ssd1306.c b/keyboards/helix/local_drivers/ssd1306.c
index 00b2fb0eec..c6fc4b7854 100644
--- a/keyboards/helix/local_drivers/ssd1306.c
+++ b/keyboards/helix/local_drivers/ssd1306.c
@@ -16,6 +16,8 @@
 #include "sendchar.h"
 #include "timer.h"
 
+struct CharacterMatrix display;
+
 // Set this to 1 to help diagnose early startup problems
 // when testing power-on with ble.  Turn it off otherwise,
 // as the latency of printing most of the debug info messes
diff --git a/keyboards/helix/local_drivers/ssd1306.h b/keyboards/helix/local_drivers/ssd1306.h
index f9f91c6fed..bcb30f8859 100644
--- a/keyboards/helix/local_drivers/ssd1306.h
+++ b/keyboards/helix/local_drivers/ssd1306.h
@@ -66,7 +66,7 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(bool rotate);
 void iota_gfx_task(void);
diff --git a/keyboards/yosino58/ssd1306.c b/keyboards/yosino58/ssd1306.c
index ff6ba210d1..abd9de2f7a 100644
--- a/keyboards/yosino58/ssd1306.c
+++ b/keyboards/yosino58/ssd1306.c
@@ -10,6 +10,8 @@
 #include "sendchar.h"
 #include "timer.h"
 
+struct CharacterMatrix display;
+
 extern const unsigned char font[] PROGMEM;
 
 // Set this to 1 to help diagnose early startup problems
diff --git a/keyboards/yosino58/ssd1306.h b/keyboards/yosino58/ssd1306.h
index acaf6217ef..35e4c144cc 100644
--- a/keyboards/yosino58/ssd1306.h
+++ b/keyboards/yosino58/ssd1306.h
@@ -70,7 +70,7 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(bool rotate);
 void iota_gfx_task(void);