diff --git a/common/filterpaper.h b/common/filterpaper.h
deleted file mode 100644
index 9598dc6..0000000
--- a/common/filterpaper.h
+++ /dev/null
@@ -1,87 +0,0 @@
-// Copyright @filterpaper
-// Copyright Christoph Cullmann
-// SPDX-License-Identifier: GPL-2.0+
-
-// Basic keycode filter for tap-hold keys
-#define GET_TAP_KEYCODE(k) ((k) & 0xff)
-
-// Tap-hold decision helper macros
-#define IS_LAYER_TAP(k)     (IS_QK_LAYER_TAP(k) && QK_LAYER_TAP_GET_LAYER(k))
-#define IS_SHORTCUT(k)      (IS_QK_LAYER_TAP(k) && !QK_LAYER_TAP_GET_LAYER(k))
-#define IS_MOD_TAP_SHIFT(k) (IS_QK_MOD_TAP(k) && (k) & (QK_LSFT))
-#define IS_MOD_TAP_CAG(k)   (IS_QK_MOD_TAP(k) && (k) & (QK_LCTL|QK_LALT|QK_LGUI))
-
-#define IS_HOMEROW(r)          (r->event.key.row == 1 || r->event.key.row == 5)
-#define IS_HOMEROW_SHIFT(k, r) (IS_HOMEROW(r) && IS_MOD_TAP_SHIFT(k))
-#define IS_HOMEROW_CAG(k, r)   (IS_HOMEROW(r) && IS_MOD_TAP_CAG(k))
-
-#define IS_TYPING(k) ((uint8_t)(k) <= KC_Z && last_input_activity_elapsed() < QUICK_TAP_TERM)
-
-#define IS_UNILATERAL(r, n) ( \
-    (r->event.key.row == 1 && 0 <= n.event.key.row && n.event.key.row <= 2) || \
-    (r->event.key.row == 5 && 4 <= n.event.key.row && n.event.key.row <= 6) )
-
-#define IS_BILATERAL(r, n) ( \
-    (r->event.key.row == 1 && 4 <= n.event.key.row && n.event.key.row <= 6) || \
-    (r->event.key.row == 5 && 0 <= n.event.key.row && n.event.key.row <= 2) )
-
-static uint_fast16_t inter_keycode;
-static keyrecord_t   inter_record;
-
-bool pre_process_record_user(uint16_t keycode, keyrecord_t *record) {
-    static bool     is_pressed[UINT8_MAX];
-    const  uint16_t tap_keycode = GET_TAP_KEYCODE(keycode);
-
-    if (record->event.pressed) {
-        // Press the tap keycode if the tap-hold key follows the previous key swiftly
-        if ((IS_HOMEROW_CAG(keycode, record) || IS_SHORTCUT(keycode)) && IS_TYPING(inter_keycode)) {
-            is_pressed[tap_keycode] = true;
-            record->keycode = tap_keycode;
-        }
-        // Cache incoming input for in-progress and subsequent tap-hold decisions
-        inter_keycode = keycode;
-        inter_record  = *record;
-    }
-
-    // Release the pressed tap keycode
-    else if (is_pressed[tap_keycode]) {
-        is_pressed[tap_keycode] = false;
-        record->keycode = tap_keycode;
-    }
-
-    return true;
-}
-
-bool get_hold_on_other_key_press(uint16_t keycode, keyrecord_t *record) {
-    // Tap the mod-tap key with an overlapping non-Shift key on the same hand
-    // or the shortcut key with any overlapping key
-    if ((IS_UNILATERAL(record, inter_record) && !IS_MOD_TAP_SHIFT(inter_keycode)) || IS_SHORTCUT(keycode)) {
-        record->tap.count++;
-        process_record(record);
-        return false;
-    }
-
-    // Activate layer hold with another key press
-    else return IS_LAYER_TAP(keycode);
-}
-
-bool get_permissive_hold(uint16_t keycode, keyrecord_t *record) {
-    // Enable Shift with a nested key press
-    return IS_MOD_TAP_SHIFT(keycode);
-}
-
-uint16_t get_tapping_term(uint16_t keycode, keyrecord_t *record) {
-    // Shorten interval for Shift
-    return IS_HOMEROW_SHIFT(keycode, record) ? SHIFT_TAP_TERM : TAPPING_TERM;
-}
-
-// Simplify unused magic config functions
-#ifndef MAGIC_ENABLE
-uint8_t mod_config(uint8_t mod) { return mod; }
-uint16_t keycode_config(uint16_t keycode) { return keycode; }
-#endif
-
-// Reduce marix scanning delay
-#ifndef DIRECT_PINS
-void matrix_io_delay(void) { __asm__ volatile("nop\nnop\nnop\n"); }
-#endif