assertFalse(labelTypeHelper.matchLocale(Locale.ENGLISH, Locale.JAPANESE));
        assertFalse(labelTypeHelper.matchLocale(Locale.SIMPLIFIED_CHINESE, Locale.TRADITIONAL_CHINESE));

        assertTrue(labelTypeHelper.matchLocale(null, Locale.ROOT));
        assertTrue(labelTypeHelper.matchLocale(Locale.ENGLISH, Locale.ROOT));
        assertTrue(labelTypeHelper.matchLocale(Locale.ROOT, Locale.ROOT));

        // Execute
        OptionalThing<Locale> result = provider.findBusinessLocale(null, mockRequestManager);

        // Verify
        assertTrue(result.isPresent());
        Locale locale = result.get();
        assertEquals("no", locale.getLanguage());
        assertEquals("NO", locale.getCountry());
        assertEquals("NY", locale.getVariant());
    }

    /**
     * Retrieves the current user's locale from the request manager.
     *
     * @return the user's locale, or Locale.ROOT if not available
     */
    private static Locale getUserLocale() {
        final Locale locale = ComponentUtil.getRequestManager().getUserLocale();
        if (locale == null) {
            return Locale.ROOT;
        }
        return locale;
    }

    /**

        // Test with various locale configurations
        Locale[] testLocales = { Locale.US, Locale.UK, Locale.CANADA, Locale.FRANCE, Locale.CHINA, Locale.KOREA, new Locale("es", "ES"),
                new Locale("pt", "BR") };

        for (Locale locale : testLocales) {
            OptionalThing<String> result = provider.determineAlias(locale);

            final String language = locale.getLanguage();
            final String country = locale.getCountry();
            if (StringUtil.isNotBlank(language)) {
                if (StringUtil.isNotBlank(country)) {
                    return language.toLowerCase(Locale.ROOT) + "-" + country.toLowerCase(Locale.ROOT);
                }

        @Override
        public void removeAttribute(String name) {
        }

        @Override
        public java.util.Locale getLocale() {
            return java.util.Locale.getDefault();
        }

        @Override
        public java.util.Enumeration<java.util.Locale> getLocales() {
            return java.util.Collections.emptyEnumeration();
        }

        @Override

        /**
         * Returns the locale.
         *
         * @return The locale.
         */
        public Locale getLocale() {
            return locale;
        }

        /**
         * Sets the locale.
         *
         * @param locale The locale.
         */
        public void setLocale(final Locale locale) {
            this.locale = locale;
        }
    }

    /**

            return null;
        }
        String target = null;
        final Locale locale = ComponentUtil.getRequestManager().getUserLocale();
        if (locale != null) {
            final String lang = locale.getLanguage();
            if (ComponentUtil.getFessConfig().isOnlineHelpSupportedLang(lang)) {
                target = lang.toUpperCase(Locale.ROOT);
            }
        }

            } catch (final Exception e) {
                logger.debug("Failed to parse locale: name={}", name, e);
            }
        }
        return OptionalObject.empty();
    }

    @Override
    public OptionalThing<Locale> getRequestedLocale(final RequestManager requestManager) {
        return OptionalObject.empty(); // means browser default
    }

# Access: http://localhost:8080/admin/?browser_lang=sv
```

## Troubleshooting

### Language doesn't appear in dropdown

- Verify both `fess_label_[locale].properties` and `fess_message_[locale].properties` exist
- Check that locale code is in `supported.languages` in `fess_config.properties`
- Regenerate Java classes: `mvn dbflute:freegen`
- Rebuild project: `mvn clean package`
- Restart Fess application