Reset stale touchpad contacts after interrupted input

touchpad-hold-tap/90-touchpad-hold-tap.lua

@@ -153,13 +153,18 @@ local function emit_action()
     return true
 end
 
+local function reset_contacts(state)
+    state.mode = "idle"
+    state.contacts = {}
+    state.anchor_slot = nil
+    state.candidate_slot = nil
+    state.candidate_anchor_x = nil
+    state.candidate_anchor_y = nil
+end
+
 local function reset_if_clear(state)
     if contact_count(state, false) == 0 then
-        state.mode = "idle"
-        state.anchor_slot = nil
-        state.candidate_slot = nil
-        state.candidate_anchor_x = nil
-        state.candidate_anchor_y = nil
+        reset_contacts(state)
     end
 end
 
@@ -178,6 +183,12 @@ local function new_contact(state, slot, tracking_id, timestamp)
 end
 
 local function handle_tracking_begin(device, state, tracking_id, timestamp)
+    if state.contacts[state.source_slot] then
+        libinput:log_debug(
+            "touchpad-hold-tap: resetting stale contact state")
+        reset_contacts(state)
+    end
+
     if state.mode == "candidate" then
         restore_candidate(device, state, "extra contact")
     end
@@ -361,6 +372,13 @@ local function handle_frame(device, frame, timestamp)
             else
                 modified = true
             end
+        elseif event.usage == evdev.BTN_TOUCH and event.value == 0 then
+            table.insert(output, event)
+            if contact_count(state, false) > 0 then
+                libinput:log_debug(
+                    "touchpad-hold-tap: resetting empty touch state")
+                reset_contacts(state)
+            end
         elseif tool_counts[event.usage] then
             if state.mode == "candidate" or override_tools then
                 local desired = tool_counts[event.usage] ==