diff --git a/keyboards/absinthe/rules.mk b/keyboards/absinthe/rules.mk
index f0b8037c91..8f534909df 100644
--- a/keyboards/absinthe/rules.mk
+++ b/keyboards/absinthe/rules.mk
@@ -11,16 +11,6 @@ MCU = atmega32u4
 #   ATmega328P   USBasp
 BOOTLOADER = atmel-dfu
 
-# If you don't know the bootloader type, then you can specify the
-# Boot Section Size in *bytes* by uncommenting out the OPT_DEFS line
-# Otherwise, delete this section
-#   Teensy halfKay      512
-#   Teensy++ halfKay    1024
-#   Atmel DFU loader    4096
-#   LUFA bootloader     4096
-#   USBaspLoader        2048
-# OPT_DEFS += -DBOOTLOADER_SIZE=4096
-
 # Build Options
 #   change yes to no to disable
 #
@@ -39,7 +29,5 @@ MIDI_ENABLE = no            # MIDI support
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
 AUDIO_ENABLE = no           # Audio output on port C6
 FAUXCLICKY_ENABLE = no      # Use buzzer to emulate clicky switches
-HD44780_ENABLE = no         # Enable support for HD44780 based LCDs
 ENCODER_ENABLE = yes
 RGBLIGHT_ENABLE = yes
-# EXTRAFLAGS += -flto
diff --git a/keyboards/hhkb/ansi/config.h b/keyboards/hhkb/ansi/config.h
index 689fd55681..53d958cc17 100644
--- a/keyboards/hhkb/ansi/config.h
+++ b/keyboards/hhkb/ansi/config.h
@@ -54,11 +54,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define SUART_IN_BIT    1
 
 #ifdef __AVR_ATmega32U4__
-    /* iom32u4.h has no definition of UCSR1D. copy from iom32u2.h */
-    #define UCSR1D _SFR_MEM8(0xCB)
-    #define RTSEN 0
-    #define CTSEN 1
-
     #define SERIAL_UART_BAUD        115200
     #define SERIAL_UART_DATA        UDR1
     #define SERIAL_UART_UBRR        ((F_CPU/(16.0*SERIAL_UART_BAUD)-1+0.5))
diff --git a/keyboards/hhkb/jp/config.h b/keyboards/hhkb/jp/config.h
index 01dab6d440..9f6819b86e 100644
--- a/keyboards/hhkb/jp/config.h
+++ b/keyboards/hhkb/jp/config.h
@@ -54,11 +54,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define SUART_IN_BIT    1
 
 #ifdef __AVR_ATmega32U4__
-    /* iom32u4.h has no definition of UCSR1D. copy from iom32u2.h */
-    #define UCSR1D _SFR_MEM8(0xCB)
-    #define RTSEN 0
-    #define CTSEN 1
-
     #define SERIAL_UART_BAUD        115200
     #define SERIAL_UART_DATA        UDR1
     #define SERIAL_UART_UBRR        ((F_CPU/(16.0*SERIAL_UART_BAUD)-1+0.5))
diff --git a/keyboards/kingly_keys/smd_milk/2_milk.c b/keyboards/kingly_keys/smd_milk/2_milk.c
deleted file mode 100644
index 95fa50e029..0000000000
--- a/keyboards/kingly_keys/smd_milk/2_milk.c
+++ /dev/null
@@ -1,16 +0,0 @@
-/* Copyright 2019 Sebastian Williams
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#include "smd_milk.h"
diff --git a/keyboards/kingly_keys/smd_milk/2_milk.h b/keyboards/kingly_keys/smd_milk/2_milk.h
deleted file mode 100644
index 8f294817f9..0000000000
--- a/keyboards/kingly_keys/smd_milk/2_milk.h
+++ /dev/null
@@ -1,26 +0,0 @@
-/* Copyright 2019 Sebastian Williams
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#pragma once
-
-#include "quantum.h"
-
-#define LAYOUT( \
-  K00,  \
-  K01  \
-) { \
-  { K00 }, \
-  { K01 } \
-}