diff --git a/src/buffer.cc b/src/buffer.cc
index 3c402905..2f80cc9c 100644
--- a/src/buffer.cc
+++ b/src/buffer.cc
@@ -453,7 +453,7 @@ ByteCoord Buffer::char_next(ByteCoord coord) const
     if (coord.column < m_lines[coord.line].length() - 1)
     {
         auto line = m_lines[coord.line];
-        coord.column += utf8::codepoint_size(line[(int)coord.column]);
+        coord.column += utf8::codepoint_size(line[coord.column]);
         // Handle invalid utf-8
         if (coord.column >= line.length())
         {
diff --git a/src/interned_string.cc b/src/interned_string.cc
index b8825f66..5afb460e 100644
--- a/src/interned_string.cc
+++ b/src/interned_string.cc
@@ -24,26 +24,32 @@ InternedString StringRegistry::acquire(StringView str)
         StringView storage_view{m_storage[slot].first.data(), (int)m_storage[slot].first.size()};
         m_slot_map[storage_view] = slot;
 
-        return InternedString{storage_view, InternedString::AlreadyAcquired{}};
+        return InternedString{storage_view, slot};
     }
 
     size_t slot = it->second;
     m_storage[slot].second++;
     StringView storage_view{m_storage[slot].first.data(), (int)m_storage[slot].first.size()};
-    return InternedString{storage_view, InternedString::AlreadyAcquired{}};
+    return InternedString{storage_view, slot};
 }
 
-void StringRegistry::release(StringView str)
+void StringRegistry::acquire(size_t slot)
 {
-    auto it = m_slot_map.find(str);
-    kak_assert(it != m_slot_map.end());
+    kak_assert(slot < m_storage.size());
+    kak_assert(m_storage[slot].second > 0);
+    ++m_storage[slot].second;
+}
 
-    size_t slot = it->second;
+void StringRegistry::release(size_t slot)
+{
     if (--m_storage[slot].second == 0)
     {
         m_free_slots.push_back(slot);
+        std::vector<char>& data = m_storage[slot].first;
+        auto it = m_slot_map.find(StringView{data.data(), (int)data.size()});
+        kak_assert(it != m_slot_map.end());
         m_slot_map.erase(it);
-        m_storage[slot].first.clear();
+        data.clear();
     }
 }
 
diff --git a/src/interned_string.hh b/src/interned_string.hh
index 23984a5d..c1bf3517 100644
--- a/src/interned_string.hh
+++ b/src/interned_string.hh
@@ -17,7 +17,8 @@ private:
     friend class InternedString;
 
     InternedString acquire(StringView str);
-    void release(StringView str);
+    void acquire(size_t slot);
+    void release(size_t slot);
 
     std::unordered_map<StringView, size_t> m_slot_map;
     std::vector<size_t> m_free_slots;
@@ -34,26 +35,34 @@ public:
 
     InternedString(InternedString&& str) : StringView(str)
     {
-        static_cast<StringView&>(str) = StringView{};
+        m_slot = str.m_slot;
+        str.m_slot = -1;
     }
 
     InternedString(const char* str) : StringView() { acquire_ifn(str); }
     InternedString(StringView str) : StringView() { acquire_ifn(str); }
-    //InternedString(const String& str) : StringView() { acquire_ifn(str); }
 
     InternedString& operator=(const InternedString& str)
     {
         if (str.data() == data() && str.length() == length())
             return *this;
-        release_ifn();
-        acquire_ifn(str);
+        static_cast<StringView&>(*this) = str;
+        if (str.m_slot != m_slot)
+        {
+            release_ifn();
+            m_slot = str.m_slot;
+            if (str.m_slot != -1)
+                StringRegistry::instance().acquire(str.m_slot);
+        }
+
         return *this;
     }
 
     InternedString& operator=(InternedString&& str)
     {
         static_cast<StringView&>(*this) = str;
-        static_cast<StringView&>(str) = StringView{};
+        m_slot = str.m_slot;
+        str.m_slot = -1;
         return *this;
     }
 
@@ -73,23 +82,27 @@ public:
 private:
     friend class StringRegistry;
 
-    struct AlreadyAcquired{};
-    InternedString(StringView str, AlreadyAcquired)
-        : StringView(str) {}
+    InternedString(StringView str, size_t slot)
+        : StringView(str), m_slot(slot) {}
 
     void acquire_ifn(StringView str)
     {
         if (str.empty())
+        {
             static_cast<StringView&>(*this) = StringView{};
+            m_slot = -1;
+        }
         else
             *this = StringRegistry::instance().acquire(str);
     }
 
     void release_ifn()
     {
-        if (!empty())
-            StringRegistry::instance().release(*this);
+        if (m_slot != -1)
+            StringRegistry::instance().release(m_slot);
     }
+
+    size_t m_slot = -1;
 };
 
 }