diff --git a/apps/openmw/mwbase/windowmanager.hpp b/apps/openmw/mwbase/windowmanager.hpp
index a972d2a320..e3a1a0c725 100644
--- a/apps/openmw/mwbase/windowmanager.hpp
+++ b/apps/openmw/mwbase/windowmanager.hpp
@@ -214,7 +214,7 @@ namespace MWBase
             /// update activated quick key state (if action executing was delayed for some reason)
             virtual void updateActivatedQuickKey () = 0;
 
-            virtual std::string getSelectedSpell() = 0;
+            virtual const std::string& getSelectedSpell() = 0;
             virtual void setSelectedSpell(const std::string& spellId, int successChancePercent) = 0;
             virtual void setSelectedEnchantItem(const MWWorld::Ptr& item) = 0;
             virtual const MWWorld::Ptr& getSelectedEnchantItem() const = 0;
diff --git a/apps/openmw/mwbase/world.hpp b/apps/openmw/mwbase/world.hpp
index d570ffe515..54f5c16e65 100644
--- a/apps/openmw/mwbase/world.hpp
+++ b/apps/openmw/mwbase/world.hpp
@@ -224,7 +224,7 @@ namespace MWBase
             virtual void advanceTime (double hours, bool incremental = false) = 0;
             ///< Advance in-game time.
 
-            virtual std::string getMonthName (int month = -1) const = 0;
+            virtual std::string_view getMonthName(int month = -1) const = 0;
             ///< Return name of month (-1: current month)
 
             virtual MWWorld::TimeStamp getTimeStamp() const = 0;
@@ -514,7 +514,7 @@ namespace MWBase
 
             /// Find default position inside exterior cell specified by name
             /// \return false if exterior with given name not exists, true otherwise
-            virtual bool findExteriorPosition(const std::string &name, ESM::Position &pos) = 0;
+            virtual bool findExteriorPosition(std::string_view name, ESM::Position& pos) = 0;
 
             /// Find default position inside interior cell specified by name
             /// \return false if interior with given name not exists, true otherwise
@@ -566,8 +566,7 @@ namespace MWBase
 
             /// Teleports \a ptr to the closest reference of \a id (e.g. DivineMarker, PrisonMarker, TempleMarker)
             /// @note id must be lower case
-            virtual void teleportToClosestMarker (const MWWorld::Ptr& ptr,
-                                                  const std::string& id) = 0;
+            virtual void teleportToClosestMarker(const MWWorld::Ptr& ptr, std::string_view id) = 0;
 
             enum DetectionType
             {
diff --git a/apps/openmw/mwgui/travelwindow.cpp b/apps/openmw/mwgui/travelwindow.cpp
index fcdc5775d1..1104653c62 100644
--- a/apps/openmw/mwgui/travelwindow.cpp
+++ b/apps/openmw/mwgui/travelwindow.cpp
@@ -126,7 +126,7 @@ namespace MWGui
             std::string cellname = transport[i].mCellName;
             bool interior = true;
             const osg::Vec2i cellIndex = MWWorld::positionToCellIndex(transport[i].mPos.pos[0], transport[i].mPos.pos[1]);
-            if (cellname == "")
+            if (cellname.empty())
             {
                 MWWorld::CellStore* cell = MWBase::Environment::get().getWorld()->getExterior(cellIndex.x(), cellIndex.y());
                 cellname = MWBase::Environment::get().getWorld()->getCellName(cell);
@@ -170,7 +170,7 @@ namespace MWGui
 
         MWBase::Environment::get().getWindowManager()->fadeScreenOut(1);
         ESM::Position pos = *_sender->getUserData<ESM::Position>();
-        std::string cellname = _sender->getUserString("Destination");
+        const std::string& cellname = _sender->getUserString("Destination");
         bool interior = _sender->getUserString("interior") == "y";
         if (mPtr.getCell()->isExterior())
         {
@@ -187,7 +187,7 @@ namespace MWGui
         MWBase::Environment::get().getWindowManager()->fadeScreenOut(1);
 
         // Teleports any followers, too.
-        MWWorld::ActionTeleport action(interior ? cellname : "", pos, true);
+        MWWorld::ActionTeleport action(interior ? cellname : std::string_view{}, pos, true);
         action.execute(player);
 
         MWBase::Environment::get().getWindowManager()->fadeScreenOut(0);
diff --git a/apps/openmw/mwgui/waitdialog.cpp b/apps/openmw/mwgui/waitdialog.cpp
index 2fe3cefb45..f6671915f3 100644
--- a/apps/openmw/mwgui/waitdialog.cpp
+++ b/apps/openmw/mwgui/waitdialog.cpp
@@ -153,7 +153,7 @@ namespace MWGui
         onHourSliderChangedPosition(mHourSlider, 0);
         mHourSlider->setScrollPosition (0);
 
-        std::string month = MWBase::Environment::get().getWorld ()->getMonthName();
+        std::string_view month = MWBase::Environment::get().getWorld ()->getMonthName();
         int hour = static_cast<int>(MWBase::Environment::get().getWorld()->getTimeStamp().getHour());
         bool pm = hour >= 12;
         if (hour >= 13) hour -= 12;
@@ -161,7 +161,7 @@ namespace MWGui
 
         ESM::EpochTimeStamp currentDate = MWBase::Environment::get().getWorld()->getEpochTimeStamp();
         std::string daysPassed = Misc::StringUtils::format("(#{sDay} %i)", MWBase::Environment::get().getWorld()->getTimeStamp().getDay());
-        std::string formattedHour(pm ? "#{sSaveMenuHelp05}" : "#{sSaveMenuHelp04}");
+        std::string_view formattedHour(pm ? "#{sSaveMenuHelp05}" : "#{sSaveMenuHelp04}");
         std::string dateTimeText = Misc::StringUtils::format("%i %s %s %i %s", currentDate.mDay, month, daysPassed, hour, formattedHour);
         mDateTimeText->setCaptionWithReplacing (dateTimeText);
     }
@@ -195,7 +195,7 @@ namespace MWGui
         MWWorld::Ptr player = world->getPlayerPtr();
         if (mSleeping && player.getCell()->isExterior())
         {
-            std::string regionstr = player.getCell()->getCell()->mRegion;
+            const std::string& regionstr = player.getCell()->getCell()->mRegion;
             if (!regionstr.empty())
             {
                 const ESM::Region *region = world->getStore().get<ESM::Region>().find (regionstr);
diff --git a/apps/openmw/mwgui/windowmanagerimp.hpp b/apps/openmw/mwgui/windowmanagerimp.hpp
index ad15831098..14a7f89115 100644
--- a/apps/openmw/mwgui/windowmanagerimp.hpp
+++ b/apps/openmw/mwgui/windowmanagerimp.hpp
@@ -242,7 +242,7 @@ namespace MWGui
     /// update activated quick key state (if action executing was delayed for some reason)
     void updateActivatedQuickKey () override;
 
-    std::string getSelectedSpell() override { return mSelectedSpell; }
+    const std::string& getSelectedSpell() override { return mSelectedSpell; }
     void setSelectedSpell(const std::string& spellId, int successChancePercent) override;
     void setSelectedEnchantItem(const MWWorld::Ptr& item) override;
     const MWWorld::Ptr& getSelectedEnchantItem() const override;
diff --git a/apps/openmw/mwmechanics/aicombataction.cpp b/apps/openmw/mwmechanics/aicombataction.cpp
index 3092363537..2def2696bb 100644
--- a/apps/openmw/mwmechanics/aicombataction.cpp
+++ b/apps/openmw/mwmechanics/aicombataction.cpp
@@ -299,7 +299,7 @@ namespace MWMechanics
         const CreatureStats& stats = actor.getClass().getCreatureStats(actor);
         const MWWorld::Store<ESM::GameSetting>& gmst = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>();
 
-        std::string selectedSpellId = stats.getSpells().getSelectedSpell();
+        const std::string& selectedSpellId = stats.getSpells().getSelectedSpell();
         MWWorld::Ptr selectedEnchItem;
 
         MWWorld::Ptr activeWeapon, activeAmmo;
diff --git a/apps/openmw/mwmechanics/character.cpp b/apps/openmw/mwmechanics/character.cpp
index 597a0c143c..e9a631bcc1 100644
--- a/apps/openmw/mwmechanics/character.cpp
+++ b/apps/openmw/mwmechanics/character.cpp
@@ -1383,7 +1383,7 @@ bool CharacterController::updateWeaponState()
                     // For the player, set the spell we want to cast
                     // This has to be done at the start of the casting animation,
                     // *not* when selecting a spell in the GUI (otherwise you could change the spell mid-animation)
-                    std::string selectedSpell = MWBase::Environment::get().getWindowManager()->getSelectedSpell();
+                    const std::string& selectedSpell = MWBase::Environment::get().getWindowManager()->getSelectedSpell();
                     stats.getSpells().setSelectedSpell(selectedSpell);
                 }
                 std::string spellid = stats.getSpells().getSelectedSpell();
diff --git a/apps/openmw/mwmechanics/mechanicsmanagerimp.cpp b/apps/openmw/mwmechanics/mechanicsmanagerimp.cpp
index 732e0fccff..bde5ad0225 100644
--- a/apps/openmw/mwmechanics/mechanicsmanagerimp.cpp
+++ b/apps/openmw/mwmechanics/mechanicsmanagerimp.cpp
@@ -533,7 +533,7 @@ namespace MWMechanics
             std::map<std::string, int>::const_iterator playerFactionIt = playerStats.getFactionRanks().begin();
             for (; playerFactionIt != playerStats.getFactionRanks().end(); ++playerFactionIt)
             {
-                std::string itFaction = playerFactionIt->first;
+                const std::string& itFaction = playerFactionIt->first;
 
                 // Ignore the faction, if a player was expelled from it.
                 if (playerStats.getExpelled(itFaction))
@@ -839,12 +839,8 @@ namespace MWMechanics
 
             for (const ESM::GameSetting &currentSetting : gameSettings)
             {
-                std::string currentGMSTID = currentSetting.mId;
-                Misc::StringUtils::lowerCaseInPlace(currentGMSTID);
-
                 // Don't bother checking this GMST if it's not a sMagicBound* one.
-                const std::string& toFind = "smagicbound";
-                if (currentGMSTID.compare(0, toFind.length(), toFind) != 0)
+                if (!Misc::StringUtils::ciStartsWith(currentSetting.mId, "smagicbound"))
                     continue;
 
                 // All sMagicBound* GMST's should be of type string
@@ -970,7 +966,7 @@ namespace MWMechanics
             return false;
 
         const OwnerMap& owners = it->second;
-        const std::string ownerid = ptr.getCellRef().getRefId();
+        const std::string& ownerid = ptr.getCellRef().getRefId();
         OwnerMap::const_iterator ownerFound = owners.find(std::make_pair(Misc::StringUtils::lowerCase(ownerid), false));
         if (ownerFound != owners.end())
             return true;
diff --git a/apps/openmw/mwmechanics/spelleffects.cpp b/apps/openmw/mwmechanics/spelleffects.cpp
index 509695c4e7..b1178fa5b2 100644
--- a/apps/openmw/mwmechanics/spelleffects.cpp
+++ b/apps/openmw/mwmechanics/spelleffects.cpp
@@ -428,7 +428,7 @@ void applyMagicEffect(const MWWorld::Ptr& target, const MWWorld::Ptr& caster, co
                 invalid = true;
             else if (world->isTeleportingEnabled())
             {
-                auto marker = (effect.mEffectId == ESM::MagicEffect::DivineIntervention) ? "divinemarker" : "templemarker";
+                std::string_view marker = (effect.mEffectId == ESM::MagicEffect::DivineIntervention) ? "divinemarker" : "templemarker";
                 world->teleportToClosestMarker(target, marker);
                 if(!caster.isEmpty())
                 {
@@ -464,7 +464,10 @@ void applyMagicEffect(const MWWorld::Ptr& target, const MWWorld::Ptr& caster, co
                 world->getPlayer().getMarkedPosition(markedCell, markedPosition);
                 if (markedCell)
                 {
-                    MWWorld::ActionTeleport action(markedCell->isExterior() ? "" : markedCell->getCell()->mName, markedPosition, false);
+                    std::string_view dest;
+                    if (!markedCell->isExterior())
+                        dest = markedCell->getCell()->mName;
+                    MWWorld::ActionTeleport action(dest, markedPosition, false);
                     action.execute(target);
                     if(!caster.isEmpty())
                     {
diff --git a/apps/openmw/mwmechanics/spells.cpp b/apps/openmw/mwmechanics/spells.cpp
index b6ca74ef6b..2f81be6d36 100644
--- a/apps/openmw/mwmechanics/spells.cpp
+++ b/apps/openmw/mwmechanics/spells.cpp
@@ -106,7 +106,7 @@ namespace MWMechanics
         mSelectedSpell = spellId;
     }
 
-    const std::string Spells::getSelectedSpell() const
+    const std::string& Spells::getSelectedSpell() const
     {
         return mSelectedSpell;
     }
diff --git a/apps/openmw/mwmechanics/spells.hpp b/apps/openmw/mwmechanics/spells.hpp
index ff803a9ec2..2dd8706b1c 100644
--- a/apps/openmw/mwmechanics/spells.hpp
+++ b/apps/openmw/mwmechanics/spells.hpp
@@ -87,7 +87,7 @@ namespace MWMechanics
             void setSelectedSpell (const std::string& spellId);
             ///< This function does not verify, if the spell is available.
 
-            const std::string getSelectedSpell() const;
+            const std::string& getSelectedSpell() const;
             ///< May return an empty string.
 
             bool hasCommonDisease() const;
diff --git a/apps/openmw/mwmechanics/summoning.cpp b/apps/openmw/mwmechanics/summoning.cpp
index 0cf2e26f47..f17b6773e8 100644
--- a/apps/openmw/mwmechanics/summoning.cpp
+++ b/apps/openmw/mwmechanics/summoning.cpp
@@ -27,9 +27,9 @@ namespace MWMechanics
              || (effectId >= ESM::MagicEffect::SummonFabricant && effectId <= ESM::MagicEffect::SummonCreature05));
     }
 
-    std::string getSummonedCreature(int effectId)
+    std::string_view getSummonedCreature(int effectId)
     {
-        static const std::map<int, std::string> summonMap
+        static const std::map<int, std::string_view> summonMap
         {
             {ESM::MagicEffect::SummonAncestralGhost, "sMagicAncestralGhostID"},
             {ESM::MagicEffect::SummonBonelord, "sMagicBonelordID"},
@@ -58,12 +58,12 @@ namespace MWMechanics
         auto it = summonMap.find(effectId);
         if (it != summonMap.end())
             return MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>().find(it->second)->mValue.getString();
-        return std::string();
+        return {};
     }
 
     int summonCreature(int effectId, const MWWorld::Ptr& summoner)
     {
-        std::string creatureID = getSummonedCreature(effectId);
+        std::string_view creatureID = getSummonedCreature(effectId);
         int creatureActorId = -1;
         if (!creatureID.empty())
         {
diff --git a/apps/openmw/mwmechanics/summoning.hpp b/apps/openmw/mwmechanics/summoning.hpp
index aff88bec13..62a5c725a3 100644
--- a/apps/openmw/mwmechanics/summoning.hpp
+++ b/apps/openmw/mwmechanics/summoning.hpp
@@ -1,7 +1,7 @@
 #ifndef OPENMW_MECHANICS_SUMMONING_H
 #define OPENMW_MECHANICS_SUMMONING_H
 
-#include <string>
+#include <string_view>
 #include <utility>
 
 #include <components/esm3/magiceffects.hpp>
@@ -15,7 +15,7 @@ namespace MWMechanics
 {
     bool isSummoningEffect(int effectId);
 
-    std::string getSummonedCreature(int effectId);
+    std::string_view getSummonedCreature(int effectId);
 
     void purgeSummonEffect(const MWWorld::Ptr& summoner, const std::pair<int, int>& summon);
 
diff --git a/apps/openmw/mwscript/cellextensions.cpp b/apps/openmw/mwscript/cellextensions.cpp
index a8d918e6cb..444e2dbced 100644
--- a/apps/openmw/mwscript/cellextensions.cpp
+++ b/apps/openmw/mwscript/cellextensions.cpp
@@ -87,7 +87,7 @@ namespace MWScript
 
                 void execute (Interpreter::Runtime& runtime) override
                 {
-                    std::string cell{runtime.getStringLiteral(runtime[0].mInteger)};
+                    std::string_view cell = runtime.getStringLiteral(runtime[0].mInteger);
                     runtime.pop();
 
                     ESM::Position pos;
@@ -96,7 +96,7 @@ namespace MWScript
 
                     if (world->findExteriorPosition(cell, pos))
                     {
-                        MWWorld::ActionTeleport("", pos, false).execute(playerPtr);
+                        MWWorld::ActionTeleport({}, pos, false).execute(playerPtr);
                         world->adjustPosition(playerPtr, false);
                     }
                     else
@@ -130,7 +130,7 @@ namespace MWScript
 
                     pos.rot[0] = pos.rot[1] = pos.rot[2] = 0;
 
-                    MWWorld::ActionTeleport("", pos, false).execute(playerPtr);
+                    MWWorld::ActionTeleport({}, pos, false).execute(playerPtr);
                     world->adjustPosition(playerPtr, false);
                 }
         };
diff --git a/apps/openmw/mwscript/guiextensions.cpp b/apps/openmw/mwscript/guiextensions.cpp
index f240747f6e..36669f34ac 100644
--- a/apps/openmw/mwscript/guiextensions.cpp
+++ b/apps/openmw/mwscript/guiextensions.cpp
@@ -114,7 +114,7 @@ namespace MWScript
 
             void execute (Interpreter::Runtime& runtime) override
             {
-                std::string cell = ::Misc::StringUtils::lowerCase(runtime.getStringLiteral(runtime[0].mInteger));
+                std::string_view cell = runtime.getStringLiteral(runtime[0].mInteger);
                 runtime.pop();
 
                 // "Will match complete or partial cells, so ShowMap, "Vivec" will show cells Vivec and Vivec, Fred's House as well."
@@ -127,9 +127,7 @@ namespace MWScript
 
                 for (auto it = cells.extBegin(); it != cells.extEnd(); ++it)
                 {
-                    std::string name = it->mName;
-                    ::Misc::StringUtils::lowerCaseInPlace(name);
-                    if (name.length() >= cell.length() && name.substr(0, cell.length()) == cell)
+                    if (Misc::StringUtils::ciStartsWith(it->mName, cell))
                         winMgr->addVisitedLocation(it->mName, it->getGridX(), it->getGridY());
                 }
             }
@@ -144,11 +142,10 @@ namespace MWScript
                 const MWWorld::Store<ESM::Cell> &cells =
                     MWBase::Environment::get().getWorld ()->getStore().get<ESM::Cell>();
 
-                MWWorld::Store<ESM::Cell>::iterator it = cells.extBegin();
-                for (; it != cells.extEnd(); ++it)
+                for (auto it = cells.extBegin(); it != cells.extEnd(); ++it)
                 {
-                    std::string name = it->mName;
-                    if (name != "")
+                    const std::string& name = it->mName;
+                    if (!name.empty())
                         MWBase::Environment::get().getWindowManager()->addVisitedLocation (
                             name,
                             it->getGridX(),
diff --git a/apps/openmw/mwscript/miscextensions.cpp b/apps/openmw/mwscript/miscextensions.cpp
index cb289d83b0..e91b211006 100644
--- a/apps/openmw/mwscript/miscextensions.cpp
+++ b/apps/openmw/mwscript/miscextensions.cpp
@@ -591,7 +591,7 @@ namespace MWScript
                 {
                     MWWorld::Ptr ptr = R()(runtime);
 
-                    std::string creature{runtime.getStringLiteral(runtime[0].mInteger)};
+                    std::string_view creature = runtime.getStringLiteral(runtime[0].mInteger);
                     runtime.pop();
 
                     std::string_view gem = runtime.getStringLiteral(runtime[0].mInteger);
diff --git a/apps/openmw/mwscript/statsextensions.cpp b/apps/openmw/mwscript/statsextensions.cpp
index 76f117f4ce..fa48ae7e99 100644
--- a/apps/openmw/mwscript/statsextensions.cpp
+++ b/apps/openmw/mwscript/statsextensions.cpp
@@ -757,7 +757,7 @@ namespace MWScript
                 {
                     MWWorld::ConstPtr ptr = R()(runtime, false);
 
-                    std::string factionId;
+                    std::string_view factionId;
 
                     if (arg0==1)
                     {
@@ -790,7 +790,7 @@ namespace MWScript
                     Interpreter::Type_Integer value = runtime[0].mInteger;
                     runtime.pop();
 
-                    std::string factionId;
+                    std::string_view factionId;
 
                     if (arg0==1)
                     {
@@ -822,7 +822,7 @@ namespace MWScript
                     Interpreter::Type_Integer value = runtime[0].mInteger;
                     runtime.pop();
 
-                    std::string factionId;
+                    std::string_view factionId;
 
                     if (arg0==1)
                     {
diff --git a/apps/openmw/mwsound/soundmanagerimp.cpp b/apps/openmw/mwsound/soundmanagerimp.cpp
index eab1ff59da..8b6c9f2ef9 100644
--- a/apps/openmw/mwsound/soundmanagerimp.cpp
+++ b/apps/openmw/mwsound/soundmanagerimp.cpp
@@ -336,7 +336,7 @@ namespace MWSound
         {
             std::vector<std::string> filelist;
             // Is there an ini setting for this filename or something?
-            std::string filename = "music/special/morrowind title.mp3";
+            std::string_view filename = "music/special/morrowind title.mp3";
             if (mVFS->exists(filename))
             {
                 filelist.emplace_back(filename);
diff --git a/apps/openmw/mwworld/actionharvest.cpp b/apps/openmw/mwworld/actionharvest.cpp
index 161d1f4e7e..aecb62a3ff 100644
--- a/apps/openmw/mwworld/actionharvest.cpp
+++ b/apps/openmw/mwworld/actionharvest.cpp
@@ -53,9 +53,9 @@ namespace MWWorld
             std::ostringstream stream;
             int lineCount = 0;
             const static int maxLines = 10;
-            for (auto & pair : takenMap)
+            for (const auto& pair : takenMap)
             {
-                std::string itemName = pair.first;
+                const std::string& itemName = pair.first;
                 int itemCount = pair.second;
                 lineCount++;
                 if (lineCount == maxLines)
diff --git a/apps/openmw/mwworld/actionteleport.cpp b/apps/openmw/mwworld/actionteleport.cpp
index 72cafc4eed..17370671a1 100644
--- a/apps/openmw/mwworld/actionteleport.cpp
+++ b/apps/openmw/mwworld/actionteleport.cpp
@@ -16,7 +16,7 @@
 
 namespace MWWorld
 {
-    ActionTeleport::ActionTeleport (const std::string& cellName,
+    ActionTeleport::ActionTeleport(std::string_view cellName,
         const ESM::Position& position, bool teleportFollowers)
     : Action (true), mCellName (cellName), mPosition (position), mTeleportFollowers(teleportFollowers)
     {
diff --git a/apps/openmw/mwworld/actionteleport.hpp b/apps/openmw/mwworld/actionteleport.hpp
index fcbf59a203..b467e1db0f 100644
--- a/apps/openmw/mwworld/actionteleport.hpp
+++ b/apps/openmw/mwworld/actionteleport.hpp
@@ -3,6 +3,7 @@
 
 #include <set>
 #include <string>
+#include <string_view>
 
 #include <components/esm/defs.hpp>
 
@@ -26,7 +27,7 @@ namespace MWWorld
 
             /// If cellName is empty, an exterior cell is assumed.
             /// @param teleportFollowers Whether to teleport any following actors of the target actor as well.
-            ActionTeleport (const std::string& cellName, const ESM::Position& position, bool teleportFollowers);
+            ActionTeleport(std::string_view cellName, const ESM::Position& position, bool teleportFollowers);
 
             /// @param includeHostiles If true, include hostile followers (which won't actually be teleported) in the output,
             ///                        e.g. so that the teleport action can calm them.
diff --git a/apps/openmw/mwworld/cellref.cpp b/apps/openmw/mwworld/cellref.cpp
index 69b6a94da8..6e0e5351dd 100644
--- a/apps/openmw/mwworld/cellref.cpp
+++ b/apps/openmw/mwworld/cellref.cpp
@@ -136,7 +136,7 @@ namespace MWWorld
         }
     }
 
-    void CellRef::setSoul(const std::string &soul)
+    void CellRef::setSoul(std::string_view soul)
     {
         if (soul != mCellRef.mSoul)
         {
diff --git a/apps/openmw/mwworld/cellref.hpp b/apps/openmw/mwworld/cellref.hpp
index c7842919a1..8f11542187 100644
--- a/apps/openmw/mwworld/cellref.hpp
+++ b/apps/openmw/mwworld/cellref.hpp
@@ -1,6 +1,8 @@
 #ifndef OPENMW_MWWORLD_CELLREF_H
 #define OPENMW_MWWORLD_CELLREF_H
 
+#include <string_view>
+
 #include <components/esm3/cellref.hpp>
 
 namespace ESM
@@ -87,7 +89,7 @@ namespace MWWorld
 
         // ID of creature trapped in this soul gem
         const std::string& getSoul() const { return mCellRef.mSoul; }
-        void setSoul(const std::string& soul);
+        void setSoul(std::string_view soul);
 
         // The faction that owns this object (and will get angry if
         // you take it and are not a faction member)
diff --git a/apps/openmw/mwworld/cells.cpp b/apps/openmw/mwworld/cells.cpp
index 457e142e18..3ad8a1ee38 100644
--- a/apps/openmw/mwworld/cells.cpp
+++ b/apps/openmw/mwworld/cells.cpp
@@ -93,7 +93,7 @@ void MWWorld::Cells::clear()
     mIdCacheIndex = 0;
 }
 
-MWWorld::Ptr MWWorld::Cells::getPtrAndCache (const std::string& name, CellStore& cellStore)
+MWWorld::Ptr MWWorld::Cells::getPtrAndCache(std::string_view name, CellStore& cellStore)
 {
     Ptr ptr = getPtr (name, cellStore);
 
@@ -226,7 +226,7 @@ MWWorld::CellStore *MWWorld::Cells::getCell (const ESM::CellId& id)
     return getInterior (id.mWorldspace);
 }
 
-MWWorld::Ptr MWWorld::Cells::getPtr (const std::string& name, CellStore& cell,
+MWWorld::Ptr MWWorld::Cells::getPtr(std::string_view name, CellStore& cell,
     bool searchInContainers)
 {
     if (cell.getState()==CellStore::State_Unloaded)
@@ -342,7 +342,7 @@ MWWorld::Ptr MWWorld::Cells::getPtr(CellStore& cellStore, const std::string& id,
     return cellStore.searchViaRefNum(refNum);
 }
 
-void MWWorld::Cells::getExteriorPtrs(const std::string &name, std::vector<MWWorld::Ptr> &out)
+void MWWorld::Cells::getExteriorPtrs(std::string_view name, std::vector<MWWorld::Ptr>& out)
 {
     const MWWorld::Store<ESM::Cell> &cells = mStore.get<ESM::Cell>();
     for (MWWorld::Store<ESM::Cell>::iterator iter = cells.extBegin(); iter != cells.extEnd(); ++iter)
diff --git a/apps/openmw/mwworld/cells.hpp b/apps/openmw/mwworld/cells.hpp
index b377d79803..65567912f3 100644
--- a/apps/openmw/mwworld/cells.hpp
+++ b/apps/openmw/mwworld/cells.hpp
@@ -42,7 +42,7 @@ namespace MWWorld
 
             CellStore *getCellStore (const ESM::Cell *cell);
 
-            Ptr getPtrAndCache (const std::string& name, CellStore& cellStore);
+            Ptr getPtrAndCache(std::string_view name, CellStore& cellStore);
 
             Ptr getPtr(CellStore& cellStore, const std::string& id, const ESM::RefNum& refNum);
 
@@ -60,7 +60,7 @@ namespace MWWorld
 
             CellStore *getCell (const ESM::CellId& id);
 
-            Ptr getPtr (const std::string& name, CellStore& cellStore, bool searchInContainers = false);
+            Ptr getPtr(std::string_view name, CellStore& cellStore, bool searchInContainers = false);
             ///< \param searchInContainers Only affect loaded cells.
             /// @note name must be lower case
 
@@ -75,7 +75,7 @@ namespace MWWorld
             /// Get all Ptrs referencing \a name in exterior cells
             /// @note Due to the current implementation of getPtr this only supports one Ptr per cell.
             /// @note name must be lower case
-            void getExteriorPtrs (const std::string& name, std::vector<MWWorld::Ptr>& out);
+            void getExteriorPtrs(std::string_view name, std::vector<MWWorld::Ptr>& out);
 
             /// Get all Ptrs referencing \a name in interior cells
             /// @note Due to the current implementation of getPtr this only supports one Ptr per cell.
diff --git a/apps/openmw/mwworld/cellstore.cpp b/apps/openmw/mwworld/cellstore.cpp
index eb674e247a..fd4c6161e9 100644
--- a/apps/openmw/mwworld/cellstore.cpp
+++ b/apps/openmw/mwworld/cellstore.cpp
@@ -36,7 +36,7 @@
 namespace
 {
     template<typename T>
-    MWWorld::Ptr searchInContainerList (MWWorld::CellRefList<T>& containerList, const std::string& id)
+    MWWorld::Ptr searchInContainerList(MWWorld::CellRefList<T>& containerList, std::string_view id)
     {
         for (typename MWWorld::CellRefList<T>::List::iterator iter (containerList.mList.begin());
              iter!=containerList.mList.end(); ++iter)
@@ -420,7 +420,7 @@ namespace MWWorld
         return mHasState;
     }
 
-    bool CellStore::hasId (const std::string& id) const
+    bool CellStore::hasId(std::string_view id) const
     {
         if (mState==State_Unloaded)
             return false;
@@ -435,10 +435,10 @@ namespace MWWorld
     struct SearchVisitor
     {
         PtrType mFound;
-        const std::string *mIdToFind;
+        std::string_view mIdToFind;
         bool operator()(const PtrType& ptr)
         {
-            if (ptr.getCellRef().getRefId() == *mIdToFind)
+            if (ptr.getCellRef().getRefId() == mIdToFind)
             {
                 mFound = ptr;
                 return false;
@@ -447,18 +447,18 @@ namespace MWWorld
         }
     };
 
-    Ptr CellStore::search (const std::string& id)
+    Ptr CellStore::search(std::string_view id)
     {
         SearchVisitor<MWWorld::Ptr> searchVisitor;
-        searchVisitor.mIdToFind = &id;
+        searchVisitor.mIdToFind = id;
         forEach(searchVisitor);
         return searchVisitor.mFound;
     }
 
-    ConstPtr CellStore::searchConst (const std::string& id) const
+    ConstPtr CellStore::searchConst(std::string_view id) const
     {
         SearchVisitor<MWWorld::ConstPtr> searchVisitor;
-        searchVisitor.mIdToFind = &id;
+        searchVisitor.mIdToFind = id;
         forEachConst(searchVisitor);
         return searchVisitor.mFound;
     }
@@ -676,7 +676,7 @@ namespace MWWorld
         return (mCell->mData.mFlags & ESM::Cell::QuasiEx) != 0;
     }
 
-    Ptr CellStore::searchInContainer (const std::string& id)
+    Ptr CellStore::searchInContainer(std::string_view id)
     {
         bool oldState = mHasState;
 
diff --git a/apps/openmw/mwworld/cellstore.hpp b/apps/openmw/mwworld/cellstore.hpp
index 5132ef4207..72d17b40dd 100644
--- a/apps/openmw/mwworld/cellstore.hpp
+++ b/apps/openmw/mwworld/cellstore.hpp
@@ -4,6 +4,7 @@
 #include <algorithm>
 #include <stdexcept>
 #include <string>
+#include <string_view>
 #include <typeinfo>
 #include <map>
 #include <memory>
@@ -224,17 +225,17 @@ namespace MWWorld
             bool hasState() const;
             ///< Does this cell have state that needs to be stored in a saved game file?
 
-            bool hasId (const std::string& id) const;
+            bool hasId(std::string_view id) const;
             ///< May return true for deleted IDs when in preload state. Will return false, if cell is
             /// unloaded.
             /// @note Will not account for moved references which may exist in Loaded state. Use search() instead if the cell is loaded.
 
-            Ptr search (const std::string& id);
+            Ptr search(std::string_view id);
             ///< Will return an empty Ptr if cell is not loaded. Does not check references in
             /// containers.
             /// @note Triggers CellStore hasState flag.
 
-            ConstPtr searchConst (const std::string& id) const;
+            ConstPtr searchConst(std::string_view id) const;
             ///< Will return an empty Ptr if cell is not loaded. Does not check references in
             /// containers.
             /// @note Does not trigger CellStore hasState flag.
@@ -372,7 +373,7 @@ namespace MWWorld
 
             bool isQuasiExterior() const;
 
-            Ptr searchInContainer (const std::string& id);
+            Ptr searchInContainer(std::string_view id);
 
             void loadState (const ESM::CellState& state);
 
diff --git a/apps/openmw/mwworld/containerstore.cpp b/apps/openmw/mwworld/containerstore.cpp
index ab55047756..f1288ee548 100644
--- a/apps/openmw/mwworld/containerstore.cpp
+++ b/apps/openmw/mwworld/containerstore.cpp
@@ -56,15 +56,13 @@ namespace
     }
 
     template<typename T>
-    MWWorld::Ptr searchId (MWWorld::CellRefList<T>& list, const std::string& id,
-        MWWorld::ContainerStore *store)
+    MWWorld::Ptr searchId(MWWorld::CellRefList<T>& list, std::string_view id, MWWorld::ContainerStore* store)
     {
         store->resolve();
-        std::string id2 = Misc::StringUtils::lowerCase (id);
 
         for (MWWorld::LiveCellRef<T>& liveCellRef : list.mList)
         {
-            if (Misc::StringUtils::ciEqual(liveCellRef.mBase->mId, id2) && liveCellRef.mData.getCount())
+            if (Misc::StringUtils::ciEqual(liveCellRef.mBase->mId, id) && liveCellRef.mData.getCount())
             {
                 MWWorld::Ptr ptr(&liveCellRef, nullptr);
                 ptr.setContainerStore (store);
@@ -760,7 +758,7 @@ MWWorld::Ptr MWWorld::ContainerStore::findReplacement(const std::string& id)
     return item;
 }
 
-MWWorld::Ptr MWWorld::ContainerStore::search (const std::string& id)
+MWWorld::Ptr MWWorld::ContainerStore::search(std::string_view id)
 {
     resolve();
     {
diff --git a/apps/openmw/mwworld/containerstore.hpp b/apps/openmw/mwworld/containerstore.hpp
index 8bbd32af0d..f7f569ec97 100644
--- a/apps/openmw/mwworld/containerstore.hpp
+++ b/apps/openmw/mwworld/containerstore.hpp
@@ -240,7 +240,7 @@ namespace MWWorld
             Ptr findReplacement(const std::string& id);
             ///< Returns replacement for object with given id. Prefer used items (with low durability left).
 
-            Ptr search (const std::string& id);
+            Ptr search(std::string_view id);
 
             virtual void writeState (ESM::InventoryState& state) const;
 
diff --git a/apps/openmw/mwworld/datetimemanager.cpp b/apps/openmw/mwworld/datetimemanager.cpp
index 67d1ce1fbc..1f62a016fd 100644
--- a/apps/openmw/mwworld/datetimemanager.cpp
+++ b/apps/openmw/mwworld/datetimemanager.cpp
@@ -139,16 +139,16 @@ namespace MWWorld
         globalVariables["year"].setInteger(mYear);
     }
 
-    std::string DateTimeManager::getMonthName(int month) const
+    std::string_view DateTimeManager::getMonthName(int month) const
     {
         if (month == -1)
             month = mMonth;
 
         const int months = 12;
         if (month < 0 || month >= months)
-            return std::string();
+            return {};
 
-        static const char *monthNames[months] =
+        static const std::string_view monthNames[months] =
         {
             "sMonthMorningstar", "sMonthSunsdawn", "sMonthFirstseed", "sMonthRainshand",
             "sMonthSecondseed", "sMonthMidyear", "sMonthSunsheight", "sMonthLastseed",
diff --git a/apps/openmw/mwworld/datetimemanager.hpp b/apps/openmw/mwworld/datetimemanager.hpp
index e48eec5184..2c3df40117 100644
--- a/apps/openmw/mwworld/datetimemanager.hpp
+++ b/apps/openmw/mwworld/datetimemanager.hpp
@@ -1,7 +1,7 @@
 #ifndef GAME_MWWORLD_DATETIMEMANAGER_H
 #define GAME_MWWORLD_DATETIMEMANAGER_H
 
-#include <string>
+#include <string_view>
 
 namespace ESM
 {
@@ -27,7 +27,7 @@ namespace MWWorld
         void setMonth(int month);
 
     public:
-        std::string getMonthName(int month) const;
+        std::string_view getMonthName(int month) const;
         TimeStamp getTimeStamp() const;
         ESM::EpochTimeStamp getEpochTimeStamp() const;
         float getTimeScaleFactor() const;
diff --git a/apps/openmw/mwworld/scene.cpp b/apps/openmw/mwworld/scene.cpp
index 1435235fa0..0dba4860f5 100644
--- a/apps/openmw/mwworld/scene.cpp
+++ b/apps/openmw/mwworld/scene.cpp
@@ -231,8 +231,7 @@ namespace
                 }
                 catch (const std::exception& e)
                 {
-                    std::string error ("failed to render '" + ptr.getCellRef().getRefId() + "': ");
-                    Log(Debug::Error) << error + e.what();
+                    Log(Debug::Error) << "failed to render '" << ptr.getCellRef().getRefId() << "': " << e.what();
                 }
             }
 
diff --git a/apps/openmw/mwworld/worldimp.cpp b/apps/openmw/mwworld/worldimp.cpp
index 3150341876..a98e1b841d 100644
--- a/apps/openmw/mwworld/worldimp.cpp
+++ b/apps/openmw/mwworld/worldimp.cpp
@@ -1,5 +1,7 @@
 #include "worldimp.hpp"
 
+#include <charconv>
+
 #include <osg/Group>
 #include <osg/ComputeBoundsVisitor>
 #include <osg/Timer>
@@ -665,7 +667,7 @@ namespace MWWorld
         return mGlobalVariables.getType (name);
     }
 
-    std::string World::getMonthName (int month) const
+    std::string_view World::getMonthName(int month) const
     {
         return mCurrentDate->getMonthName(month);
     }
@@ -1418,7 +1420,10 @@ namespace MWWorld
             esmPos.pos[0] = traced.x();
             esmPos.pos[1] = traced.y();
             esmPos.pos[2] = traced.z();
-            MWWorld::ActionTeleport(actor.getCell()->isExterior() ? "" : actor.getCell()->getCell()->mName, esmPos, false).execute(actor);
+            std::string_view cell;
+            if (!actor.getCell()->isExterior())
+                cell = actor.getCell()->getCell()->mName;
+            MWWorld::ActionTeleport(cell, esmPos, false).execute(actor);
         }
     }
 
@@ -1860,7 +1865,7 @@ namespace MWWorld
 
     void World::preloadSpells()
     {
-        std::string selectedSpell = MWBase::Environment::get().getWindowManager()->getSelectedSpell();
+        const std::string& selectedSpell = MWBase::Environment::get().getWindowManager()->getSelectedSpell();
         if (!selectedSpell.empty())
         {
             const ESM::Spell* spell = mStore.get<ESM::Spell>().search(selectedSpell);
@@ -2839,29 +2844,29 @@ namespace MWWorld
         return false;
     }
 
-    bool World::findExteriorPosition(const std::string &name, ESM::Position &pos)
+    bool World::findExteriorPosition(std::string_view name, ESM::Position& pos)
     {
         pos.rot[0] = pos.rot[1] = pos.rot[2] = 0;
 
         const ESM::Cell *ext = getExterior(name);
-
-        if (!ext && name.find(',') != std::string::npos) {
-            try {
-                int x = std::stoi(name.substr(0, name.find(',')));
-                int y = std::stoi(name.substr(name.find(',')+1));
-                ext = getExterior(x, y)->getCell();
-            }
-            catch (const std::invalid_argument&)
+        if (!ext)
+        {
+            size_t comma = name.find(',');
+            if (comma != std::string::npos)
             {
-                // This exception can be ignored, as this means that name probably refers to a interior cell instead of comma separated coordinates
-            }
-            catch (const std::out_of_range&)
-            {
-                throw std::runtime_error("Cell coordinates out of range.");
+                int x, y;
+                std::from_chars_result xResult = std::from_chars(name.data(), name.data() + comma, x);
+                std::from_chars_result yResult = std::from_chars(name.data() + comma + 1, name.data() + name.size(), y);
+                if (xResult.ec == std::errc::result_out_of_range || yResult.ec == std::errc::result_out_of_range)
+                    throw std::runtime_error("Cell coordinates out of range.");
+                else if (xResult.ec == std::errc{} && yResult.ec == std::errc{})
+                    ext = getExterior(x, y)->getCell();
+                // ignore std::errc::invalid_argument, as this means that name probably refers to a interior cell instead of comma separated coordinates
             }
         }
 
-        if (ext) {
+        if (ext)
+        {
             int x = ext->getGridX();
             int y = ext->getGridY();
             indexToPosition(x, y, pos.pos[0], pos.pos[1], true);
@@ -2977,7 +2982,7 @@ namespace MWWorld
         MWWorld::SpellCastState result = MWWorld::SpellCastState::Success;
         bool isPlayer = (actor == getPlayerPtr());
 
-        std::string selectedSpell = stats.getSpells().getSelectedSpell();
+        const std::string& selectedSpell = stats.getSpells().getSelectedSpell();
 
         if (!selectedSpell.empty())
         {
@@ -3108,7 +3113,7 @@ namespace MWWorld
             }
         }
 
-        std::string selectedSpell = stats.getSpells().getSelectedSpell();
+        const std::string& selectedSpell = stats.getSpells().getSelectedSpell();
 
         MWMechanics::CastSpell cast(actor, target, false, manualSpell);
         cast.mHitPosition = hitPosition;
@@ -3268,7 +3273,7 @@ namespace MWWorld
                     }
                     else
                     {
-                        std::string dest = ref.mRef.getDestCell();
+                        const std::string& dest = ref.mRef.getDestCell();
                         if ( !checkedCells.count(dest) && !currentCells.count(dest) )
                             nextCells.insert(dest);
                     }
@@ -3282,7 +3287,7 @@ namespace MWWorld
         return false;
     }
 
-    MWWorld::ConstPtr World::getClosestMarker( const MWWorld::Ptr &ptr, const std::string &id )
+    MWWorld::ConstPtr World::getClosestMarker(const MWWorld::ConstPtr& ptr, std::string_view id)
     {
         if ( ptr.getCell()->isExterior() ) {
             return getClosestMarkerFromExteriorPosition(mPlayer->getLastKnownExteriorPosition(), id);
@@ -3323,7 +3328,7 @@ namespace MWWorld
                     }
                     else
                     {
-                        std::string dest = ref.mRef.getDestCell();
+                        const std::string& dest = ref.mRef.getDestCell();
                         if ( !checkedCells.count(dest) && !currentCells.count(dest) )
                             nextCells.insert(dest);
                     }
@@ -3333,7 +3338,7 @@ namespace MWWorld
         return MWWorld::Ptr();
     }
 
-    MWWorld::ConstPtr World::getClosestMarkerFromExteriorPosition( const osg::Vec3f& worldPos, const std::string &id ) {
+    MWWorld::ConstPtr World::getClosestMarkerFromExteriorPosition(const osg::Vec3f& worldPos, std::string_view id) {
         MWWorld::ConstPtr closestMarker;
         float closestDistance = std::numeric_limits<float>::max();
 
@@ -3374,8 +3379,7 @@ namespace MWWorld
             mCells.recharge(duration);
     }
 
-    void World::teleportToClosestMarker (const MWWorld::Ptr& ptr,
-                                          const std::string& id)
+    void World::teleportToClosestMarker(const MWWorld::Ptr& ptr, std::string_view id)
     {
         MWWorld::ConstPtr closestMarker = getClosestMarker( ptr, id );
 
@@ -3385,7 +3389,7 @@ namespace MWWorld
             return;
         }
 
-        std::string cellName;
+        std::string_view cellName;
         if ( !closestMarker.mCell->isExterior() )
             cellName = closestMarker.mCell->getCell()->mName;
 
@@ -3584,7 +3588,7 @@ namespace MWWorld
             Log(Debug::Warning) << "Failed to confiscate items: no closest prison marker found.";
             return;
         }
-        std::string prisonName = prisonMarker.getCellRef().getDestCell();
+        const std::string& prisonName = prisonMarker.getCellRef().getDestCell();
         if ( prisonName.empty() )
         {
             Log(Debug::Warning) << "Failed to confiscate items: prison marker not linked to prison interior";
@@ -3751,7 +3755,7 @@ namespace MWWorld
             else
                 areaStatic = mStore.get<ESM::Static>().find ("VFX_DefaultArea");
 
-            std::string texture = effect->mParticle;
+            const std::string& texture = effect->mParticle;
 
             if (effectInfo.mArea <= 0)
             {
diff --git a/apps/openmw/mwworld/worldimp.hpp b/apps/openmw/mwworld/worldimp.hpp
index db563a7c7b..d3d2ab82e1 100644
--- a/apps/openmw/mwworld/worldimp.hpp
+++ b/apps/openmw/mwworld/worldimp.hpp
@@ -182,8 +182,8 @@ namespace MWWorld
             float feetToGameUnits(float feet);
             float getActivationDistancePlusTelekinesis();
 
-            MWWorld::ConstPtr getClosestMarker( const MWWorld::Ptr &ptr, const std::string &id );
-            MWWorld::ConstPtr getClosestMarkerFromExteriorPosition( const osg::Vec3f& worldPos, const std::string &id );
+            MWWorld::ConstPtr getClosestMarker(const MWWorld::ConstPtr& ptr, std::string_view id);
+            MWWorld::ConstPtr getClosestMarkerFromExteriorPosition(const osg::Vec3f& worldPos, std::string_view id);
 
         public:
             // FIXME
@@ -320,7 +320,7 @@ namespace MWWorld
             void advanceTime (double hours, bool incremental = false) override;
             ///< Advance in-game time.
 
-            std::string getMonthName (int month = -1) const override;
+            std::string_view getMonthName(int month = -1) const override;
             ///< Return name of month (-1: current month)
 
             TimeStamp getTimeStamp() const override;
@@ -612,7 +612,7 @@ namespace MWWorld
 
             /// Find center of exterior cell above land surface
             /// \return false if exterior with given name not exists, true otherwise
-            bool findExteriorPosition(const std::string &name, ESM::Position &pos) override;
+            bool findExteriorPosition(std::string_view name, ESM::Position& pos) override;
 
             /// Find position in interior cell near door entrance
             /// \return false if interior with given name not exists, true otherwise
@@ -667,8 +667,7 @@ namespace MWWorld
 
             /// Teleports \a ptr to the closest reference of \a id (e.g. DivineMarker, PrisonMarker, TempleMarker)
             /// @note id must be lower case
-            void teleportToClosestMarker (const MWWorld::Ptr& ptr,
-                                                  const std::string& id) override;
+            void teleportToClosestMarker(const MWWorld::Ptr& ptr, std::string_view id) override;
 
             /// List all references (filtered by \a type) detected by \a ptr. The range
             /// is determined by the current magnitude of the "Detect X" magic effect belonging to \a type.