diff --git a/Docs/PERFORMANCE.md b/Docs/PERFORMANCE.md
new file mode 100644
index 0000000..83002a4
--- /dev/null
+++ b/Docs/PERFORMANCE.md
@@ -0,0 +1,60 @@
+# Performance notes
+
+## Player cache (`ShaguTweaks_player_cache`)
+
+The account-wide player cache feeds Social Colors, Chat Levels and the
+nameplate/chat class colors. It is read at every login and `/reload` and
+written at every logout, so its size is a direct load-time and memory cost.
+Earlier versions let it grow without limit; one account reached 4.1 MB.
+
+`libs/libunitscan.lua` now owns expiry and runs it once per session, at the
+first loading screen:
+
+| Entry | Kept for |
+|---|---|
+| Player whose class is known | 180 days after last sighting |
+| Player whose class was never learned | 90 days after last sighting |
+| Whole cache | at most 10,000 players; the oldest sightings go first |
+
+- Every sighting refreshes the age: mouseover, target, nameplate, party,
+  raid, guild roster, friend list, `/who` and chat.
+- Guild members and friends are refreshed by their roster events every
+  session, so they do not expire while they stay in the guild or friend list.
+- Entries saved before this change have no age. They are dated from the
+  cache's existing grace start (`players_cleanup`), as the old Social Colors
+  cleanup did. The first login after the update can remove many entries.
+- A player's GUID is saved only while the class is unknown. Such entries are
+  resolved later with `GetPlayerInfoByGUID` when the engine knows the GUID.
+
+The separate 180-day cleanup in Social Colors is removed. It ran only every
+180 days and only while that module was enabled.
+
+## Event handling
+
+- Chat: a speaker whose class is known and who spoke within the hour needs
+  no GUID lookup or write.
+- Guild roster: a full rescan runs at most once a minute unless the member
+  count changed. Many addons request the roster every few seconds.
+- Mouseover, target, nameplate and group sightings skip `UnitGUID` when
+  `UnitClass` already gave the class.
+- A name missing from the cache queries ClassicAPI's player cache once
+  instead of twice.
+
+## Range Color
+
+The module shared Blizzard's `rangeTimer` and tested it against 0.2 seconds.
+Once the timer had reset, that test was always true, so the full range check
+ran on every frame for every ranged action button. It now keeps its own
+0.2-second timer. Blizzard's own range check runs again, so the hotkey text
+turns red out of range, as in the default UI.
+
+## Not changed
+
+- Health Numbers and Big Health use one-shot deferred updates only.
+- Both castbars update only while visible; Energy Tick hides at full mana
+  out of combat.
+- Free Slot Count counts slots once per `BAG_UPDATE_DELAYED`. Disable it if a
+  bag addon already shows the count.
+
+Nothing here has been measured in game yet. To compare before and after, see
+[Measuring performance](CLASSICAPI_UPDATES.md#measuring-performance).
diff --git a/README.md b/README.md
index 3f456ba..4b7e204 100644
--- a/README.md
+++ b/README.md
@@ -179,6 +179,7 @@ For detailed provenance and licensing information, see:
 - [PROJECT_IDENTITY.md](PROJECT_IDENTITY.md)
 - [Docs/ASSET_PROVENANCE.md](Docs/ASSET_PROVENANCE.md)
 - [Docs/MODERN_MANA.md](Docs/MODERN_MANA.md)
+- [Docs/PERFORMANCE.md](Docs/PERFORMANCE.md) — player cache limits and other performance notes
 - [Docs/UPSTREAM_README.md](Docs/UPSTREAM_README.md) — the Dusk fork's README, kept for reference
 - [LICENSES/](LICENSES)
 
diff --git a/libs/libunitscan.lua b/libs/libunitscan.lua
index c2150fd..7eb7960 100644
--- a/libs/libunitscan.lua
+++ b/libs/libunitscan.lua
@@ -5,7 +5,15 @@ local API = ShaguTweaks.API
 
 local units = { players = {}, mobs = {} }
 local queue = { }
-local PASSIVE_CACHE_TTL = 90 * 24 * 60 * 60
+
+-- Player cache limits. ShaguTweaks_player_cache is parsed at every login and
+-- written at every logout, so its size is a direct load-time and memory cost.
+local DAY = 24 * 60 * 60
+local PASSIVE_CACHE_TTL = 90 * DAY   -- players whose class was never learned
+local KNOWN_CACHE_TTL = 180 * DAY    -- every other player, counted from last sighting
+local MAX_CACHED_PLAYERS = 10000     -- oldest sightings go first above this
+local CHAT_REFRESH = 60 * 60         -- re-resolve a known chat speaker at most hourly
+local GUILD_SCAN_INTERVAL = 60       -- seconds between full guild roster scans
 
 local libunitscan = CreateFrame("Frame", "ShaguTweaksUnitScan", UIParent)
 
@@ -289,21 +297,46 @@ end
 
 ShaguTweaks.GetPlayerCache = EnsurePlayerCache
 
-local function EnrichPlayerFromClassicAPI(name)
-  if not name or not API or not API.GetCachedPlayerInfoByName then return end
+-- Same player name, ignoring case. Compare first so the common exact match
+-- does not create two lowercase strings.
+local function SameName(a, b)
+  return a == b or string.lower(a) == string.lower(b)
+end
 
-  local _, class, _, _, _, _, _, guid = API.GetCachedPlayerInfoByName(name)
-  class = class and class ~= "" and class or nil
-  guid = guid and guid ~= "" and guid or nil
-  if not class and not guid then return end
+-- New player records carry a timestamp from the start, so the login cleanup
+-- can age every entry, not only chat-only ones.
+local function GetOrCreatePlayer(name)
+  local data = units.players[name]
+  if not data then
+    data = { lastseen_ts = time() }
+    units.players[name] = data
+  end
+  return data
+end
 
-  -- Keep ShaguTweaks keyed by the exact name it already knows. This avoids
-  -- duplicate SavedVariable entries if another cache normalizes name casing.
-  units.players[name] = units.players[name] or {}
-  units.players[name].class = class or units.players[name].class
-  units.players[name].guid = guid or units.players[name].guid
+-- Store a class. A GUID is kept only while the class is unknown: it is then
+-- the one way to learn it later through GetPlayerInfoByGUID. Known players
+-- need no GUID in SavedVariables, and nothing else reads it.
+local function SetPlayerClass(data, class, guid)
+  if class then data.class = class end
+  if data.class then
+    data.guid = nil
+  elseif guid then
+    data.guid = guid
+  end
+end
 
-  return name
+-- A class-less entry that kept its GUID: ask the engine's name cache.
+local function EnrichPlayerFromStoredGUID(name, data)
+  if not data or data.class or not data.guid then return end
+  if not API or not API.GetPlayerInfoByGUID then return end
+
+  local _, class, _, _, _, apiName = API.GetPlayerInfoByGUID(data.guid)
+  if not class or class == "" or not apiName or apiName == "" then return end
+  if not SameName(apiName, name) then return end
+
+  SetPlayerClass(data, class)
+  return true
 end
 
 local function EnrichPlayerFromCurrentChat(name)
@@ -319,11 +352,9 @@ local function EnrichPlayerFromCurrentChat(name)
   local _, class, _, _, _, apiName = API.GetPlayerInfoByGUID(guid)
   class = class and class ~= "" and class or nil
   if not apiName or apiName == "" or not class then return end
-  if string.lower(apiName) ~= string.lower(name) then return end
+  if not SameName(apiName, name) then return end
 
-  units.players[name] = units.players[name] or {}
-  units.players[name].class = class
-  units.players[name].guid = guid
+  SetPlayerClass(GetOrCreatePlayer(name), class, guid)
 
   return name
 end
@@ -333,34 +364,41 @@ function ShaguTweaks.GetUnitData(name, active)
 
   EnsurePlayerCache()
 
-  -- Persistent ClassicAPI data can answer class-only queries without making
-  -- another SavedVariables record. Keep our level and social history fields.
-  if (not units.players[name] or not units.players[name].class)
-    and API and API.HasPersistentPlayerCache and API.HasPersistentPlayerCache() then
-    local _, class, _, _, _, resolvedName, _, guid = API.GetCachedPlayerInfoByName(name)
-    if class and class ~= "" and resolvedName
-      and string.lower(resolvedName) == string.lower(name)
+  local data = units.players[name]
+
+  if (not data or not data.class) and not EnrichPlayerFromStoredGUID(name, data) then
+    -- ClassicAPI's player cache by name. Query it once: the persistent-storage
+    -- check below and the plain enrichment both use the same result.
+    local class, guid, resolvedName, _
+    if API and API.GetCachedPlayerInfoByName then
+      _, class, _, _, _, resolvedName, _, guid = API.GetCachedPlayerInfoByName(name)
+      class = class and class ~= "" and class or nil
+      guid = guid and guid ~= "" and guid or nil
+    end
+
+    -- Persistent ClassicAPI data can answer class-only queries without making
+    -- another SavedVariables record. Keep our level and social history fields.
+    if class and resolvedName and SameName(resolvedName, name)
+      and API.HasPersistentPlayerCache and API.HasPersistentPlayerCache()
       and API.RememberPlayerInfo(resolvedName, class, guid) then
-      local data = units.players[name]
       return class, data and data.level, data and data.elite, true
     end
-  end
 
-  if not units["players"][name] then
-    EnrichPlayerFromClassicAPI(name)
-    if not units["players"][name] then
-      EnrichPlayerFromCurrentChat(name)
+    -- Keep ShaguTweaks keyed by the exact name it already knows. This avoids
+    -- duplicate SavedVariable entries if another cache normalizes name casing.
+    if class or guid then
+      data = GetOrCreatePlayer(name)
+      SetPlayerClass(data, class, guid)
     end
-  elseif not units["players"][name].class then
-    EnrichPlayerFromClassicAPI(name)
-    if not units["players"][name].class then
+
+    if not data or not data.class then
       EnrichPlayerFromCurrentChat(name)
+      data = units.players[name]
     end
   end
 
-  if units["players"][name] then
-    local ret = units["players"][name]
-    return ret.class, ret.level, ret.elite, true
+  if data then
+    return data.class, data.level, data.elite, true
   end
 
   if units["mobs"][name] then
@@ -372,13 +410,28 @@ function ShaguTweaks.GetUnitData(name, active)
   end
 end
 
-local function AddData(db, name, class, level, elite, guid)
+local function AddData(db, name, class, level, elite, guid, now)
   if not name then return end
-  units[db][name] = units[db][name] or {}
-  units[db][name].class = class or units[db][name].class
-  units[db][name].level = level or units[db][name].level
-  units[db][name].elite = elite or units[db][name].elite
-  units[db][name].guid = guid or units[db][name].guid
+
+  local data = units[db][name]
+  if not data then
+    data = {}
+    units[db][name] = data
+  end
+
+  if level then data.level = level end
+  if elite then data.elite = elite end
+
+  if db == "players" then
+    SetPlayerClass(data, class, guid)
+    -- Every sighting refreshes the cache age. "lastseen" stays the chat and
+    -- friend-list date that Social Colors shows; this is only for expiry.
+    data.lastseen_ts = now or time()
+  else
+    if class then data.class = class end
+    if guid then data.guid = guid end
+  end
+
   queue[name] = nil
 end
 
@@ -387,6 +440,17 @@ local function RememberPlayer(name)
 
   EnsurePlayerCache()
 
+  local now = time()
+  local data = units.players[name]
+
+  -- Busy channels repeat the same speakers. A speaker whose class is known
+  -- and who was already seen in chat within the hour needs no GUID lookup
+  -- and no write.
+  if data and data.class and type(data.lastseen) == "number"
+    and now - data.lastseen < CHAT_REFRESH then
+    return
+  end
+
   -- ClassicAPI exposes the GUID of the CHAT_MSG_* sender synchronously.
   -- Resolve class from the engine's existing name cache only: this is a pure
   -- cache read and never sends a /who or any other network query.
@@ -401,29 +465,68 @@ local function RememberPlayer(name)
 
   -- Skip only NEW chat-only records after native persistent storage succeeds.
   -- Existing records may contain levels/history and must retain timestamps.
-  if not units.players[name] and API and API.RememberPlayerInfo
+  if not data and API and API.RememberPlayerInfo
     and API.RememberPlayerInfo(name, class, guid) then return end
 
-  units.players[name] = units.players[name] or {}
-  units.players[name].class = class or units.players[name].class
-  units.players[name].guid = guid or units.players[name].guid
-  local now = time()
-  units.players[name].lastseen = now
-  units.players[name].lastseen_ts = now
+  data = GetOrCreatePlayer(name)
+  SetPlayerClass(data, class, guid)
+  data.lastseen = now
+  data.lastseen_ts = now
 end
 
-local function PrunePassivePlayers()
+-- One pass per session, at the first PLAYER_ENTERING_WORLD.
+local function PrunePlayers(realmdb)
+  local players = units.players
   local now = time()
 
-  for name, data in pairs(units.players) do
-    -- Normalize any empty legacy/API class token back to an unknown value.
-    if data and data.class == "" then data.class = nil end
+  -- Entries written before every sighting carried a timestamp have no age.
+  -- Date them from the cache's grace start, as the old Social Colors cleanup
+  -- did, so they expire on schedule unless the player is seen again.
+  local graceStart = tonumber(realmdb.players_cleanup)
+  if not graceStart then
+    graceStart = now
+    realmdb.players_cleanup = now
+  end
 
-    -- Keep every player whose class was learned. Only anonymous/passive chat
-    -- entries expire, and only when they carry our numeric last-seen timestamp.
-    if data and not data.class and data.lastseen_ts and
-      now - data.lastseen_ts > PASSIVE_CACHE_TTL then
-      units.players[name] = nil
+  local count = 0
+  for name, data in pairs(players) do
+    if type(data) ~= "table" then
+      players[name] = nil
+    else
+      -- Normalize any empty legacy/API class token back to an unknown value.
+      if data.class == "" then data.class = nil end
+      if data.class then data.guid = nil end
+
+      local seen = GetPlayerTimestamp(data)
+      if not seen then
+        seen = graceStart
+        data.lastseen_ts = graceStart
+      end
+
+      local ttl = data.class and KNOWN_CACHE_TTL or PASSIVE_CACHE_TTL
+      if now - seen > ttl then
+        players[name] = nil
+      else
+        count = count + 1
+      end
+    end
+  end
+
+  -- Hard cap: drop the oldest sightings. Guild members and friends are
+  -- refreshed by their roster events every session, so they stay.
+  if count > MAX_CACHED_PLAYERS then
+    local stamps, n = {}, 0
+    for _, data in pairs(players) do
+      n = n + 1
+      stamps[n] = GetPlayerTimestamp(data) or 0
+    end
+    table.sort(stamps)
+
+    local cutoff = stamps[n - MAX_CACHED_PLAYERS]
+    for name, data in pairs(players) do
+      if (GetPlayerTimestamp(data) or 0) <= cutoff then
+        players[name] = nil
+      end
     end
   end
 end
@@ -446,6 +549,15 @@ local passiveChatEvents = {
 }
 
 local useNameplateUnitEvents = API and API.nameplateevents
+local prunedThisSession = false
+local lastGuildScan, lastGuildCount
+
+-- A GUID is only stored for players whose class is unknown, so skip the call
+-- when UnitClass already answered.
+local function GUIDIfClassless(unit, class)
+  if class or not API or not API.UnitGUID then return end
+  return API.UnitGUID(unit)
+end
 
 libunitscan:RegisterEvent("PLAYER_ENTERING_WORLD")
 libunitscan:RegisterEvent("PLAYER_LOGOUT")
@@ -479,18 +591,21 @@ libunitscan:SetScript("OnEvent", function()
     -- Ensure the saved database is already bound even if another module queried
     -- it earlier while restoring UI state. From here onward SavedVariables are
     -- settled, so future cache reads can skip migration checks completely.
-    EnsurePlayerCache()
+    local _, realmdb = EnsurePlayerCache()
     cacheMigrationFinalized = true
 
-    -- One cheap cleanup pass at login. Known classes are kept forever.
-    PrunePassivePlayers()
+    -- PLAYER_ENTERING_WORLD also fires at every loading screen. Expire and
+    -- cap the cache once per session only.
+    if not prunedThisSession then
+      prunedThisSession = true
+      PrunePlayers(realmdb)
+    end
 
     -- update own character details
     local name = UnitName("player")
     local _, class = UnitClass("player")
     local level = UnitLevel("player")
-    local guid = API and API.UnitGUID and API.UnitGUID("player")
-    AddData("players", name, class, level, nil, guid)
+    AddData("players", name, class, level, nil, GUIDIfClassless("player", class))
 
   elseif event == "NAME_PLATE_UNIT_ADDED" then
     -- ClassicAPI exposes an exact nameplateN unit token here. Cache players
@@ -502,8 +617,7 @@ libunitscan:SetScript("OnEvent", function()
       local name = UnitName(unit)
       local _, class = UnitClass(unit)
       local level = UnitLevel(unit)
-      local guid = API and API.UnitGUID and API.UnitGUID(unit)
-      AddData("players", name, class, level, nil, guid)
+      AddData("players", name, class, level, nil, GUIDIfClassless(unit, class))
     end
 
   elseif passiveChatEvents[event] then
@@ -513,48 +627,60 @@ libunitscan:SetScript("OnEvent", function()
 
   elseif event == "FRIENDLIST_UPDATE" then
     local name, class, level
+    local now = time()
     for i = 1, GetNumFriends() do
       name, level, class = GetFriendInfo(i)
       class = L["class"][class] or nil
       -- friendlist updates due to friend going off-line return level 0, let's not overwrite good older values
       level = level > 0 and level or nil
-      AddData("players", name, class, level)
+      AddData("players", name, class, level, nil, nil, now)
     end
 
   elseif event == "GUILD_ROSTER_UPDATE" then
-    local name, class, level, _
-    for i = 1, GetNumGuildMembers() do
-      name, _, _, level, class = GetGuildRosterInfo(i)
-      class = L["class"][class] or nil
-      AddData("players", name, class, level)
+    -- Many addons request the roster every few seconds. A class and level
+    -- cache gains nothing from rescanning a large guild each time, so scan
+    -- at most once a minute unless the member count changed.
+    local count = GetNumGuildMembers()
+    local now = time()
+    if count > 0 and not (lastGuildScan and count == lastGuildCount
+      and now - lastGuildScan < GUILD_SCAN_INTERVAL) then
+      lastGuildScan, lastGuildCount = now, count
+
+      local name, class, level, _
+      for i = 1, count do
+        name, _, _, level, class = GetGuildRosterInfo(i)
+        class = L["class"][class] or nil
+        AddData("players", name, class, level, nil, nil, now)
+      end
     end
 
   elseif event == "RAID_ROSTER_UPDATE" then
     local name, class, SubGroup, level, _
+    local now = time()
     for i = 1, GetNumRaidMembers() do
       name, _, SubGroup, level, class = GetRaidRosterInfo(i)
       class = L["class"][class] or nil
-      local guid = API and API.UnitGUID and API.UnitGUID("raid" .. i)
-      AddData("players", name, class, level, nil, guid)
+      AddData("players", name, class, level, nil, GUIDIfClassless("raid" .. i, class), now)
     end
 
   elseif event == "PARTY_MEMBERS_CHANGED" then
     local name, class, level, unit, _
+    local now = time()
     for i = 1, GetNumPartyMembers() do
       unit = "party" .. i
       _, class = UnitClass(unit)
       name = UnitName(unit)
       level = UnitLevel(unit)
-      local guid = API and API.UnitGUID and API.UnitGUID(unit)
-      AddData("players", name, class, level, nil, guid)
+      AddData("players", name, class, level, nil, GUIDIfClassless(unit, class), now)
     end
 
   elseif event == "WHO_LIST_UPDATE" then
     local name, class, level, _
+    local now = time()
     for i = 1, GetNumWhoResults() do
       name, _, level, _, class, _ = GetWhoInfo(i)
       class = L["class"][class] or nil
-      AddData("players", name, class, level)
+      AddData("players", name, class, level, nil, nil, now)
     end
 
   elseif event == "UPDATE_MOUSEOVER_UNIT" or event == "PLAYER_TARGET_CHANGED" then
@@ -564,8 +690,7 @@ libunitscan:SetScript("OnEvent", function()
       _, class = UnitClass(scan)
       level = UnitLevel(scan)
       name = UnitName(scan)
-      local guid = API and API.UnitGUID and API.UnitGUID(scan)
-      AddData("players", name, class, level, nil, guid)
+      AddData("players", name, class, level, nil, GUIDIfClassless(scan, class))
     else
       _, class = UnitClass(scan)
       elite = UnitClassification(scan)
diff --git a/mods/actionbar-range-color.lua b/mods/actionbar-range-color.lua
index 82981d8..6dd3665 100644
--- a/mods/actionbar-range-color.lua
+++ b/mods/actionbar-range-color.lua
@@ -50,14 +50,28 @@ local function GetActionRange(action)
     return NormalizeRange(IsActionInRange(action))
 end
 
+local RANGE_INTERVAL = TOOLTIP_UPDATE_TIME or 0.2
+
 module.enable = function(self)
     hooksecurefunc("ActionButton_OnUpdate", function(elapsed)
+        -- Blizzard sets rangeTimer only for actions that have a range. Use our
+        -- own countdown instead of sharing it: decrementing rangeTimer here and
+        -- testing "<= 0.2" ran this check on every frame for every ranged
+        -- button, and kept Blizzard's own range check from ever firing.
         if this.rangeTimer then
-            this.rangeTimer = this.rangeTimer - elapsed
-            if this.rangeTimer <= 0.2 then
+            local timer = (this.shaguRangeTimer or 0) - (elapsed or 0)
+            if timer > 0 then
+                this.shaguRangeTimer = timer
+            else
+                this.shaguRangeTimer = RANGE_INTERVAL
                 local action = ActionButton_GetPagedID(this)
                 local inRange = GetActionRange(action)
-                local icon = _G[this:GetName() .. "Icon"]
+                -- Look the icon up once instead of building its name each time.
+                local icon = this.shaguRangeIcon
+                if not icon then
+                    icon = _G[this:GetName() .. "Icon"]
+                    this.shaguRangeIcon = icon
+                end
 
                 if icon then
                     if inRange == 0 then
@@ -78,8 +92,6 @@ module.enable = function(self)
                         end
                     end
                 end
-
-                this.rangeTimer = TOOLTIP_UPDATE_TIME
             end
         end
     end, true)
diff --git a/mods/social-colors.lua b/mods/social-colors.lua
index b88626f..778ff25 100644
--- a/mods/social-colors.lua
+++ b/mods/social-colors.lua
@@ -10,7 +10,6 @@ local GetExpansion = ShaguTweaks.GetExpansion
 local cmatch = ShaguTweaks.cmatch
 local rgbhex = ShaguTweaks.rgbhex
 local friendinfo = gsub(gsub(FRIENDS_LEVEL_TEMPLATE,"%%s","%%s %%s"),"%%d","%%s")
-local PLAYER_CACHE_MAX_AGE = 180 * 24 * 60 * 60
 
 local function TouchPlayer(entry)
   if not entry then return end
@@ -56,43 +55,6 @@ local function GetCachedFriendDisplay(data, name)
   return cname, clevel
 end
 
-local function CleanupPlayerDB(playerdb, realmdb)
-  if not time then return end
-
-  local now = time()
-  local lastCleanup = tonumber(realmdb.players_cleanup) or 0
-
-  -- Start the 180-day grace period without touching existing entries.
-  if lastCleanup == 0 then
-    realmdb.players_cleanup = now
-    return
-  end
-
-  if now - lastCleanup < PLAYER_CACHE_MAX_AGE then return end
-
-  for name, data in pairs(playerdb) do
-    if type(data) ~= "table" then
-      playerdb[name] = nil
-    else
-      -- The shared cache also contains libunitscan-only entries. Prefer the
-      -- numeric Social Colors timestamp, then the passive scanner timestamp.
-      -- Entries without either timestamp have survived a full grace period and
-      -- can safely expire just like the old per-character cache did.
-      local lastSeen = type(data.lastseen) == "number" and data.lastseen or nil
-      local lastSeenTs = tonumber(data.lastseen_ts)
-      if lastSeenTs and (not lastSeen or lastSeenTs > lastSeen) then
-        lastSeen = lastSeenTs
-      end
-
-      if not lastSeen or now - lastSeen >= PLAYER_CACHE_MAX_AGE then
-        playerdb[name] = nil
-      end
-    end
-  end
-
-  realmdb.players_cleanup = now
-end
-
 local module = ShaguTweaks:register({
   title = T["Social Colors"],
   description = T["Show class colors in Who, Guild, Friends and Chat."],
@@ -182,16 +144,10 @@ module.enable = function(self)
   HookChatColors()
 
   local socialmod = CreateFrame("Frame", "ShaguTweaksSocialMod", UIParent)
-  socialmod:RegisterEvent("PLAYER_ENTERING_WORLD")
+  -- Cache expiry lives in libs/libunitscan.lua, which runs whether or not
+  -- this module is enabled.
   socialmod:RegisterEvent("CHAT_MSG_SYSTEM")
   socialmod:SetScript("OnEvent", function()
-    if event == "PLAYER_ENTERING_WORLD" then
-      local playerdb, realmdb = GetPlayerCache()
-      CleanupPlayerDB(playerdb, realmdb)
-      this:UnregisterEvent("PLAYER_ENTERING_WORLD")
-      return
-    end
-
     local currentdb = GetPlayerCache()
     local name = cmatch(arg1, _G.ERR_FRIEND_ONLINE_SS) or cmatch(arg1, _G.ERR_FRIEND_OFFLINE_S)
     if name and currentdb[name] then