This is very confusing as seen in #12974 or #12906. My suggestion would be "legacy."
"minified-pre",
  gulp.series(
    "buildnumber",
    "default_preferences",
    "locale",
    function scripting() {
      var defines = builder.merge(DEFINES, { MINIFIED: true, GENERIC: true });
      return createTemporaryScriptingBundle(defines);
    },
    function () {
      console.log();
      console.log("### Creating minified viewer");
      var defines = builder.merge(DEFINES, { MINIFIED: true, GENERIC: true });
      return buildMinified(defines, MINIFIED_DIR);
    }
  )
);
gulp.task(
  "minified-es5-pre",
  gulp.series(
    "buildnumber",
    "default_preferences",
    "locale",
    function scripting() {
      var defines = builder.merge(DEFINES, {
        MINIFIED: true,
        GENERIC: true,
        SKIP_BABEL: false,
      });
      return createTemporaryScriptingBundle(defines);