diff --git a/src/saveload/gamelog_sl.cpp b/src/saveload/gamelog_sl.cpp
--- a/src/saveload/gamelog_sl.cpp
+++ b/src/saveload/gamelog_sl.cpp
@@ -14,6 +14,7 @@
 
 #include "../gamelog_internal.h"
 #include "../fios.h"
+#include "../string_func.h"
 
 #include "../safeguards.h"
 
@@ -21,8 +22,8 @@
 class SlGamelogMode : public DefaultSaveLoadHandler<SlGamelogMode, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, mode.mode,         SLE_UINT8),
-		SLE_VAR(LoggedChange, mode.landscape,    SLE_UINT8),
+		SLE_VARNAME(LoggedChangeMode, mode,      "mode.mode",      SLE_UINT8),
+		SLE_VARNAME(LoggedChangeMode, landscape, "mode.landscape", SLE_UINT8),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_mode_sl_compat;
 
@@ -43,11 +44,15 @@ public:
 
 class SlGamelogRevision : public DefaultSaveLoadHandler<SlGamelogRevision, LoggedChange> {
 public:
+	static const size_t GAMELOG_REVISION_LENGTH = 15;
+	static char revision_text[GAMELOG_REVISION_LENGTH];
+
 	inline static const SaveLoad description[] = {
-		SLE_ARR(LoggedChange, revision.text,     SLE_UINT8,  GAMELOG_REVISION_LENGTH),
-		SLE_VAR(LoggedChange, revision.newgrf,   SLE_UINT32),
-		SLE_VAR(LoggedChange, revision.slver,    SLE_UINT16),
-		SLE_VAR(LoggedChange, revision.modified, SLE_UINT8),
+		    SLEG_CONDARR("revision.text", SlGamelogRevision::revision_text,   SLE_UINT8, GAMELOG_REVISION_LENGTH, SL_MIN_VERSION,     SLV_STRING_GAMELOG),
+		SLE_CONDSSTRNAME(LoggedChangeRevision, text,     "revision.text",     SLE_STR,                            SLV_STRING_GAMELOG, SL_MAX_VERSION),
+		     SLE_VARNAME(LoggedChangeRevision, newgrf,   "revision.newgrf",   SLE_UINT32),
+		     SLE_VARNAME(LoggedChangeRevision, slver,    "revision.slver",    SLE_UINT16),
+		     SLE_VARNAME(LoggedChangeRevision, modified, "revision.modified", SLE_UINT8),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_revision_sl_compat;
 
@@ -61,16 +66,23 @@ public:
 	{
 		if (lc->ct != GLCT_REVISION) return;
 		SlObject(lc, this->GetLoadDescription());
+
+		if (IsSavegameVersionBefore(SLV_STRING_GAMELOG)) {
+			StrMakeValidInPlace(SlGamelogRevision::revision_text, lastof(SlGamelogRevision::revision_text));
+			static_cast<LoggedChangeRevision *>(lc)->text = SlGamelogRevision::revision_text;
+		}
 	}
 
 	void LoadCheck(LoggedChange *lc) const override { this->Load(lc); }
 };
 
+/* static */ char SlGamelogRevision::revision_text[GAMELOG_REVISION_LENGTH];
+
 class SlGamelogOldver : public DefaultSaveLoadHandler<SlGamelogOldver, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, oldver.type,       SLE_UINT32),
-		SLE_VAR(LoggedChange, oldver.version,    SLE_UINT32),
+		SLE_VARNAME(LoggedChangeOldVersion, type,    "oldver.type",    SLE_UINT32),
+		SLE_VARNAME(LoggedChangeOldVersion, version, "oldver.version", SLE_UINT32),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_oldver_sl_compat;
 
@@ -92,9 +104,9 @@ public:
 class SlGamelogSetting : public DefaultSaveLoadHandler<SlGamelogSetting, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_STR(LoggedChange, setting.name,      SLE_STR,    128),
-		SLE_VAR(LoggedChange, setting.oldval,    SLE_INT32),
-		SLE_VAR(LoggedChange, setting.newval,    SLE_INT32),
+		SLE_SSTRNAME(LoggedChangeSettingChanged, name,   "setting.name",   SLE_STR),
+		 SLE_VARNAME(LoggedChangeSettingChanged, oldval, "setting.oldval", SLE_INT32),
+		 SLE_VARNAME(LoggedChangeSettingChanged, newval, "setting.newval", SLE_INT32),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_setting_sl_compat;
 
@@ -116,8 +128,8 @@ public:
 class SlGamelogGrfadd : public DefaultSaveLoadHandler<SlGamelogGrfadd, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, grfadd.grfid,      SLE_UINT32    ),
-		SLE_ARR(LoggedChange, grfadd.md5sum,     SLE_UINT8,  16),
+		SLE_VARNAME(LoggedChangeGRFAdd, grfid,  "grfadd.grfid",  SLE_UINT32    ),
+		SLE_ARRNAME(LoggedChangeGRFAdd, md5sum, "grfadd.md5sum", SLE_UINT8,  16),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_grfadd_sl_compat;
 
@@ -139,7 +151,7 @@ public:
 class SlGamelogGrfrem : public DefaultSaveLoadHandler<SlGamelogGrfrem, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, grfrem.grfid,      SLE_UINT32),
+		SLE_VARNAME(LoggedChangeGRFRemoved, grfid, "grfrem.grfid", SLE_UINT32),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_grfrem_sl_compat;
 
@@ -161,8 +173,8 @@ public:
 class SlGamelogGrfcompat : public DefaultSaveLoadHandler<SlGamelogGrfcompat, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, grfcompat.grfid,   SLE_UINT32    ),
-		SLE_ARR(LoggedChange, grfcompat.md5sum,  SLE_UINT8,  16),
+		SLE_VARNAME(LoggedChangeGRFChanged, grfid,  "grfcompat.grfid",  SLE_UINT32    ),
+		SLE_ARRNAME(LoggedChangeGRFChanged, md5sum, "grfcompat.md5sum", SLE_UINT8,  16),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_grfcompat_sl_compat;
 
@@ -184,7 +196,7 @@ public:
 class SlGamelogGrfparam : public DefaultSaveLoadHandler<SlGamelogGrfparam, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, grfparam.grfid,    SLE_UINT32),
+		SLE_VARNAME(LoggedChangeGRFParameterChanged, grfid, "grfparam.grfid", SLE_UINT32),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_grfparam_sl_compat;
 
@@ -206,8 +218,8 @@ public:
 class SlGamelogGrfmove : public DefaultSaveLoadHandler<SlGamelogGrfmove, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, grfmove.grfid,     SLE_UINT32),
-		SLE_VAR(LoggedChange, grfmove.offset,    SLE_INT32),
+		SLE_VARNAME(LoggedChangeGRFMoved, grfid,  "grfmove.grfid",  SLE_UINT32),
+		SLE_VARNAME(LoggedChangeGRFMoved, offset, "grfmove.offset", SLE_INT32),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_grfmove_sl_compat;
 
@@ -229,9 +241,9 @@ public:
 class SlGamelogGrfbug : public DefaultSaveLoadHandler<SlGamelogGrfbug, LoggedChange> {
 public:
 	inline static const SaveLoad description[] = {
-		SLE_VAR(LoggedChange, grfbug.data,       SLE_UINT64),
-		SLE_VAR(LoggedChange, grfbug.grfid,      SLE_UINT32),
-		SLE_VAR(LoggedChange, grfbug.bug,        SLE_UINT8),
+		SLE_VARNAME(LoggedChangeGRFBug, data,  "grfbug.data",  SLE_UINT64),
+		SLE_VARNAME(LoggedChangeGRFBug, grfid, "grfbug.grfid", SLE_UINT32),
+		SLE_VARNAME(LoggedChangeGRFBug, bug,   "grfbug.bug",   SLE_UINT8),
 	};
 	inline const static SaveLoadCompatTable compat_description = _gamelog_grfbug_sl_compat;
 
@@ -278,6 +290,27 @@ public:
 	void LoadCheck(LoggedChange *lc) const override { this->Load(lc); }
 };
 
+static std::unique_ptr<LoggedChange> MakeLoggedChange(GamelogChangeType type)
+{
+	switch (type) {
+		case GLCT_MODE:      return std::make_unique<LoggedChangeMode>();
+		case GLCT_REVISION:  return std::make_unique<LoggedChangeRevision>();
+		case GLCT_OLDVER:    return std::make_unique<LoggedChangeOldVersion>();
+		case GLCT_SETTING:   return std::make_unique<LoggedChangeSettingChanged>();
+		case GLCT_GRFADD:    return std::make_unique<LoggedChangeGRFAdd>();
+		case GLCT_GRFREM:    return std::make_unique<LoggedChangeGRFRemoved>();
+		case GLCT_GRFCOMPAT: return std::make_unique<LoggedChangeGRFChanged>();
+		case GLCT_GRFPARAM:  return std::make_unique<LoggedChangeGRFParameterChanged>();
+		case GLCT_GRFMOVE:   return std::make_unique<LoggedChangeGRFMoved>();
+		case GLCT_GRFBUG:    return std::make_unique<LoggedChangeGRFBug>();
+		case GLCT_EMERGENCY: return std::make_unique<LoggedChangeEmergencySave>();
+		case GLCT_END:
+		case GLCT_NONE:
+		default:
+			SlErrorCorrupt("Invalid gamelog action type");
+	}
+}
+
 class SlGamelogAction : public DefaultSaveLoadHandler<SlGamelogAction, LoggedAction> {
 public:
 	inline static const SaveLoad description[] = {
@@ -301,22 +334,25 @@ public:
 		SlSetStructListLength(la->change.size());
 
 		for (auto &lc : la->change) {
-			assert((uint)lc.ct < GLCT_END);
-			SlObject(&lc, this->GetDescription());
+			assert(lc->ct < GLCT_END);
+			SlObject(lc.get(), this->GetDescription());
 		}
 	}
 
+	void LoadChange(LoggedAction *la, GamelogChangeType type) const
+	{
+		std::unique_ptr<LoggedChange> lc = MakeLoggedChange(type);
+		SlObject(lc.get(), this->GetLoadDescription());
+		la->change.push_back(std::move(lc));
+	}
+
 	void Load(LoggedAction *la) const override
 	{
 		if (IsSavegameVersionBefore(SLV_RIFF_TO_ARRAY)) {
 			byte type;
 			while ((type = SlReadByte()) != GLCT_NONE) {
 				if (type >= GLCT_END) SlErrorCorrupt("Invalid gamelog change type");
-				GamelogChangeType ct = (GamelogChangeType)type;
-
-				LoggedChange &lc = la->change.emplace_back();
-				lc.ct = ct;
-				SlObject(&lc, this->GetLoadDescription());
+				LoadChange(la, (GamelogChangeType)type);
 			}
 			return;
 		}
@@ -325,9 +361,7 @@ public:
 		la->change.reserve(length);
 
 		for (size_t i = 0; i < length; i++) {
-			LoggedChange &lc = la->change.emplace_back();
-			lc.ct = (GamelogChangeType)SlReadByte();
-			SlObject(&lc, this->GetLoadDescription());
+			LoadChange(la, (GamelogChangeType)SlReadByte());
 		}
 	}