5 files changed, 73 insertions, 8 deletions
diff --git a/quantum/process_keycode/process_combo.c b/quantum/process_keycode/process_combo.c
index 2c6c9d0d5f..d3c3b1673c 100644
--- a/quantum/process_keycode/process_combo.c
+++ b/quantum/process_keycode/process_combo.c
@@ -28,6 +28,7 @@ static uint16_t timer = 0;
 static uint8_t current_combo_index = 0;
 static bool drop_buffer = false;
 static bool is_active = false;
+static bool b_combo_enable = true; // defaults to enabled
 
 static uint8_t buffer_size = 0;
 #ifdef COMBO_ALLOW_ACTION_KEYS
@@ -128,6 +129,23 @@ bool process_combo(uint16_t keycode, keyrecord_t *record) {
   drop_buffer = false;
   bool no_combo_keys_pressed = true;
 
+  if (keycode == CMB_ON && record->event.pressed) {
+    combo_enable();
+    return true;
+  }
+
+  if (keycode == CMB_OFF && record->event.pressed) {
+    combo_disable();
+    return true;
+  }
+
+  if (keycode == CMB_TOG && record->event.pressed) {
+    combo_toggle();
+    return true;
+  }
+
+  if (!is_combo_enabled()) { return true; }
+
   for (current_combo_index = 0; current_combo_index < COMBO_COUNT;
        ++current_combo_index) {
     combo_t *combo = &key_combos[current_combo_index];
@@ -166,7 +184,7 @@ bool process_combo(uint16_t keycode, keyrecord_t *record) {
 }
 
 void matrix_scan_combo(void) {
-  if (is_active && timer && timer_elapsed(timer) > COMBO_TERM) {
+  if (b_combo_enable && is_active && timer && timer_elapsed(timer) > COMBO_TERM) {
 
     /* This disables the combo, meaning key events for this
      * combo will be handled by the next processors in the chain
@@ -175,3 +193,26 @@ void matrix_scan_combo(void) {
     dump_key_buffer(true);
   }
 }
+
+void combo_enable(void) {
+    b_combo_enable = true;
+}
+
+void combo_disable(void) {
+    b_combo_enable = is_active = false;
+    timer = 0;
+    dump_key_buffer(true);
+
+}
+
+void combo_toggle(void) {
+    if (b_combo_enable) {
+        combo_disable();
+    } else {
+        combo_enable();
+    }
+}
+
+bool is_combo_enabled(void) {
+    return b_combo_enable;
+}
diff --git a/quantum/process_keycode/process_combo.h b/quantum/process_keycode/process_combo.h
index f06d2d3454..aab2849572 100644
--- a/quantum/process_keycode/process_combo.h
+++ b/quantum/process_keycode/process_combo.h
@@ -58,4 +58,9 @@ bool process_combo(uint16_t keycode, keyrecord_t *record);
 void matrix_scan_combo(void);
 void process_combo_event(uint8_t combo_index, bool pressed);
 
+void combo_enable(void);
+void combo_disable(void);
+void combo_toggle(void);
+bool is_combo_enabled(void);
+
 #endif
diff --git a/quantum/process_keycode/process_leader.c b/quantum/process_keycode/process_leader.c
index 897e9eabf6..f787e6b017 100644
--- a/quantum/process_keycode/process_leader.c
+++ b/quantum/process_keycode/process_leader.c
@@ -17,6 +17,7 @@
 #ifdef LEADER_ENABLE
 
 #include "process_leader.h"
+#include <string.h>
 
 #ifndef LEADER_TIMEOUT
   #define LEADER_TIMEOUT 300
@@ -41,11 +42,7 @@ void qk_leader_start(void) {
   leading = true;
   leader_time = timer_read();
   leader_sequence_size = 0;
-  leader_sequence[0] = 0;
-  leader_sequence[1] = 0;
-  leader_sequence[2] = 0;
-  leader_sequence[3] = 0;
-  leader_sequence[4] = 0;
+  memset(leader_sequence, 0, sizeof(leader_sequence));
 }
 
 bool process_leader(uint16_t keycode, keyrecord_t *record) {
@@ -58,8 +55,13 @@ bool process_leader(uint16_t keycode, keyrecord_t *record) {
           keycode = keycode & 0xFF;
         }
 #endif // LEADER_KEY_STRICT_KEY_PROCESSING
-        leader_sequence[leader_sequence_size] = keycode;
-        leader_sequence_size++;
+        if ( leader_sequence_size < ( sizeof(leader_sequence) / sizeof(leader_sequence[0]) ) ) {
+          leader_sequence[leader_sequence_size] = keycode;
+          leader_sequence_size++;
+        } else {
+          leading = false;
+          leader_end();
+        }
 #ifdef LEADER_PER_KEY_TIMING
         leader_time = timer_read();
 #endif
diff --git a/quantum/process_keycode/process_space_cadet.c b/quantum/process_keycode/process_space_cadet.c
index 089199eee2..c8721d446c 100644
--- a/quantum/process_keycode/process_space_cadet.c
+++ b/quantum/process_keycode/process_space_cadet.c
@@ -81,11 +81,17 @@
 
 static uint8_t sc_last = 0;
 static uint16_t sc_timer = 0;
+#ifdef SPACE_CADET_MODIFIER_CARRYOVER
+static uint8_t sc_mods = 0;
+#endif
 
 void perform_space_cadet(keyrecord_t *record, uint8_t holdMod, uint8_t tapMod, uint8_t keycode) {
   if (record->event.pressed) {
     sc_last = holdMod;
     sc_timer = timer_read ();
+#ifdef SPACE_CADET_MODIFIER_CARRYOVER
+    sc_mods = get_mods();
+#endif
     if (IS_MOD(holdMod)) {
       register_mods(MOD_BIT(holdMod));
     }
@@ -100,7 +106,13 @@ void perform_space_cadet(keyrecord_t *record, uint8_t holdMod, uint8_t tapMod, u
           register_mods(MOD_BIT(tapMod));
         }
       }
+#ifdef SPACE_CADET_MODIFIER_CARRYOVER
+    set_weak_mods(sc_mods);
+#endif
       tap_code(keycode);
+#ifdef SPACE_CADET_MODIFIER_CARRYOVER
+    clear_weak_mods();
+#endif
       if (IS_MOD(tapMod)) {
         unregister_mods(MOD_BIT(tapMod));
       }
diff --git a/quantum/process_keycode/process_ucis.c b/quantum/process_keycode/process_ucis.c
index 5de2e41fc3..fd4508b535 100644
--- a/quantum/process_keycode/process_ucis.c
+++ b/quantum/process_keycode/process_ucis.c
@@ -64,6 +64,10 @@ void qk_ucis_symbol_fallback (void) {
   }
 }
 
+__attribute__((weak))
+void qk_ucis_cancel(void) {
+}
+
 void register_ucis(const char *hex) {
   for(int i = 0; hex[i]; i++) {
     uint8_t kc = 0;
@@ -130,6 +134,7 @@ bool process_ucis (uint16_t keycode, keyrecord_t *record) {
 
     if (keycode == KC_ESC) {
       qk_ucis_state.in_progress = false;
+      qk_ucis_cancel();
       return false;
     }