Crash log: Suppress messages from internal faults

src/openttd.cpp

@@ -168,6 +168,8 @@ void CDECL usererror(const char *s, ...)
  */
 void CDECL error(const char *s, ...)
 {
+	if (CrashLog::HaveAlreadyCrashed()) DoOSAbort();
+
 	va_list va;
 	char buf[2048];
 
@@ -186,6 +188,8 @@ void CDECL error(const char *s, ...)
 
 void CDECL assert_msg_error(int line, const char *file, const char *expr, const char *extra, const char *str, ...)
 {
+	if (CrashLog::HaveAlreadyCrashed()) DoOSAbort();
+
 	va_list va;
 	char buf[2048];
 
@@ -200,7 +204,9 @@ void CDECL assert_msg_error(int line, const char *file, const char *expr, const
 	vseprintf(b, lastof(buf), str, va);
 	va_end(va);
 
-	ShowOSErrorBox(buf, true);
+	if (VideoDriver::GetInstance() == nullptr || VideoDriver::GetInstance()->HasGUI()) {
+		ShowOSErrorBox(buf, true);
+	}
 
 	/* Set the error message for the crash log and then invoke it. */
 	CrashLog::SetErrorMessage(buf);