Merge branch 'master' into jgrpp

# Conflicts:
#	.github/workflows/release-windows.yml
#	src/company_base.h
#	src/company_cmd.cpp
#	src/company_gui.cpp
#	src/console_cmds.cpp
#	src/economy.cpp
#	src/economy_cmd.h
#	src/fios.h
#	src/goal.cpp
#	src/group_gui.cpp
#	src/network/core/config.h
#	src/network/network_admin.cpp
#	src/newgrf_config.cpp
#	src/os/windows/win32.cpp
#	src/saveload/afterload.cpp
#	src/saveload/company_sl.cpp
#	src/saveload/saveload.cpp
#	src/saveload/saveload_error.hpp
#	src/settings_gui.cpp
#	src/ship_cmd.cpp
#	src/stdafx.h
#	src/story.cpp
#	src/story_base.h
#	src/string.cpp
#	src/table/settings/economy_settings.ini
#	src/tests/CMakeLists.txt
#	src/tests/math_func.cpp

src/saveload/saveload_common.h

@@ -405,8 +405,8 @@ void SlSkipBytes(size_t length);
 size_t SlGetBytesRead();
 size_t SlGetBytesWritten();
 
-void NORETURN SlError(StringID string, const char *extra_msg = nullptr, bool already_malloced = false);
-void NORETURN SlErrorCorrupt(const char *msg, bool already_malloced = false);
+void NORETURN SlError(StringID string, std::string extra_msg = {});
+void NORETURN SlErrorCorrupt(std::string msg);
 void NORETURN CDECL SlErrorCorruptFmt(const char *format, ...) WARN_FORMAT(1, 2);
 
 bool SaveLoadFileTypeIsScenario();