diff --git a/src/modules/locale/Tests.cpp b/src/modules/locale/Tests.cpp
index 23f9b5b3e..db5751177 100644
--- a/src/modules/locale/Tests.cpp
+++ b/src/modules/locale/Tests.cpp
@@ -11,7 +11,9 @@
 #include "LocaleConfiguration.h"
 #include "timezonewidget/TimeZoneImage.h"
 
+#include "Settings.h"
 #include "locale/TimeZone.h"
+#include "locale/TranslationsModel.h"
 #include "utils/Logger.h"
 
 #include <QtTest/QtTest>
@@ -43,6 +45,15 @@ private Q_SLOTS:
     void testLanguageDetection_data();
     void testLanguageDetection();
     void testLanguageDetectionValencia();
+
+    // Check realistic language mapping for issue 2008
+    void testKDENeonLanguageData();
+    void testLanguageMapping_data();
+    void testLanguageMapping();
+
+private:
+    QStringList m_KDEneonLocales;
+    QStringList m_FreeBSDLocales;
 };
 
 QTEST_MAIN( LocaleTests )
@@ -55,6 +66,12 @@ LocaleTests::~LocaleTests() {}
 void
 LocaleTests::initTestCase()
 {
+    Logger::setupLogLevel( Logger::LOGDEBUG );
+    const auto* settings = Calamares::Settings::instance();
+    if ( !settings )
+    {
+        (void)new Calamares::Settings( true );
+    }
 }
 
 void
@@ -353,6 +370,78 @@ LocaleTests::testLanguageDetectionValencia()
     }
 }
 
+static QStringList
+splitTestFileIntoLines( const QString& filename )
+{
+    // BUILD_AS_TEST is the source-directory path
+    const QFileInfo fi( QString( "%1/tests/%2" ).arg( BUILD_AS_TEST, filename ) );
+    const QString path = fi.absoluteFilePath();
+    QFile testData( path );
+    if ( testData.open( QIODevice::ReadOnly ) )
+    {
+        return QString::fromUtf8( testData.readAll() ).split( '\n', Qt::SkipEmptyParts );
+    }
+    return QStringList {};
+}
+
+void
+LocaleTests::testKDENeonLanguageData()
+{
+    const QStringList neonLocales = splitTestFileIntoLines( QStringLiteral( "locale-data-neon" ) );
+    cDebug() << "Loaded KDE neon locales test data" << neonLocales.front() << "to" << neonLocales.back();
+    QCOMPARE( neonLocales.length(), 318 );  // wc -l tells me 318 lines
+
+    m_KDEneonLocales = neonLocales;
+}
+
+void
+LocaleTests::testLanguageMapping_data()
+{
+    QTest::addColumn< QString >( "selectedLanguage" );
+    QTest::addColumn< QString >( "KDEneonLanguage" );
+
+    // Tired of writing QString or QStringLiteral all the time.
+    auto l = []( const char* p ) { return QString::fromUtf8( p ); };
+
+    // The KDEneon columns include the .UTF-8 from the source data
+    //
+    // Each column shows how a language -- which can be selected from the
+    // welcome page, and is inserted into GS as the language key that
+    // Calamares knows -- should be mapped to a supported system locale.
+    //
+    // All the mappings are for ".. in NL", which can trigger minor variation
+    // if there are languages with a _NL variant (e.g. nl_NL and nl_BE).
+
+    // clang-format off
+    QTest::newRow( "en   " ) << l( "en" )           << l( "en_US.UTF-8" );
+    QTest::newRow( "en_GB" ) << l( "en_GB" )        << l( "en_GB.UTF-8" );
+    QTest::newRow( "ca   " ) << l( "ca" )           << l( "ca_ES.UTF-8" );
+    QTest::newRow( "ca@vl" ) << l( "ca@valencia" )  << l( "ca_ES@valencia" );
+    QTest::newRow( "sr   " ) << l( "sr" )           << l( "sr_RS" );
+    QTest::newRow( "sr@lt" ) << l( "sr@latin" )     << l( "sr_RS@latin" );
+    QTest::newRow( "pt_PT" ) << l( "pt_PT" )        << l( "pt_PT.UTF-8" );
+    QTest::newRow( "pt_BR" ) << l( "pt_BR" )        << l( "pt_BR.UTF-8" );
+    QTest::newRow( "nl   " ) << l( "nl" )           << l( "nl_NL.UTF-8" );
+    QTest::newRow( "zh_TW" ) << l( "zh_TW" )        << l( "zh_TW.UTF-8" );
+    // clang-format on
+}
+
+
+void
+LocaleTests::testLanguageMapping()
+{
+    QVERIFY( !m_KDEneonLocales.isEmpty() );
+
+    QFETCH( QString, selectedLanguage );
+    QFETCH( QString, KDEneonLanguage );
+
+    QVERIFY( Calamares::Locale::availableLanguages().contains( selectedLanguage ) );
+
+    const auto r = LocaleConfiguration::fromLanguageAndLocation(
+        ( selectedLanguage ), m_KDEneonLocales, QStringLiteral( "NL" ) );
+    QCOMPARE( r.language(), KDEneonLanguage );
+}
+
 
 #include "utils/moc-warnings.h"
 
diff --git a/src/modules/locale/tests/locale-data-neon b/src/modules/locale/tests/locale-data-neon
new file mode 100644
index 000000000..0f0254d01
--- /dev/null
+++ b/src/modules/locale/tests/locale-data-neon
@@ -0,0 +1,318 @@
+aa_DJ.UTF-8
+aa_ER
+aa_ER@saaho
+aa_ET
+af_ZA.UTF-8
+agr_PE
+ak_GH
+am_ET
+an_ES.UTF-8
+anp_IN
+ar_AE.UTF-8
+ar_BH.UTF-8
+ar_DZ.UTF-8
+ar_EG.UTF-8
+ar_IN
+ar_IQ.UTF-8
+ar_JO.UTF-8
+ar_KW.UTF-8
+ar_LB.UTF-8
+ar_LY.UTF-8
+ar_MA.UTF-8
+ar_OM.UTF-8
+ar_QA.UTF-8
+ar_SA.UTF-8
+ar_SD.UTF-8
+ar_SS
+ar_SY.UTF-8
+ar_TN.UTF-8
+ar_YE.UTF-8
+ayc_PE
+az_AZ
+az_IR
+as_IN
+ast_ES.UTF-8
+be_BY.UTF-8
+be_BY@latin
+bem_ZM
+ber_DZ
+ber_MA
+bg_BG.UTF-8
+bhb_IN.UTF-8
+bho_IN
+bho_NP
+bi_VU
+bn_BD
+bn_IN
+bo_CN
+bo_IN
+br_FR.UTF-8
+brx_IN
+bs_BA.UTF-8
+byn_ER
+ca_AD.UTF-8
+ca_ES.UTF-8
+ca_ES@valencia
+ca_FR.UTF-8
+ca_IT.UTF-8
+ce_RU
+ckb_IQ
+chr_US
+cmn_TW
+crh_UA
+cs_CZ.UTF-8
+csb_PL
+cv_RU
+cy_GB.UTF-8
+da_DK.UTF-8
+de_AT.UTF-8
+de_BE.UTF-8
+de_CH.UTF-8
+de_DE.UTF-8
+de_IT.UTF-8
+de_LI.UTF-8
+de_LU.UTF-8
+doi_IN
+dsb_DE
+dv_MV
+dz_BT
+el_GR.UTF-8
+el_CY.UTF-8
+en_AG
+en_AU.UTF-8
+en_BW.UTF-8
+en_CA.UTF-8
+en_DK.UTF-8
+en_GB.UTF-8
+en_HK.UTF-8
+en_IE.UTF-8
+en_IL
+en_IN
+en_NG
+en_NZ.UTF-8
+en_PH.UTF-8
+en_SC.UTF-8
+en_SG.UTF-8
+en_US.UTF-8
+en_ZA.UTF-8
+en_ZM
+en_ZW.UTF-8
+eo
+eo_US.UTF-8
+es_AR.UTF-8
+es_BO.UTF-8
+es_CL.UTF-8
+es_CO.UTF-8
+es_CR.UTF-8
+es_CU
+es_DO.UTF-8
+es_EC.UTF-8
+es_ES.UTF-8
+es_GT.UTF-8
+es_HN.UTF-8
+es_MX.UTF-8
+es_NI.UTF-8
+es_PA.UTF-8
+es_PE.UTF-8
+es_PR.UTF-8
+es_PY.UTF-8
+es_SV.UTF-8
+es_US.UTF-8
+es_UY.UTF-8
+es_VE.UTF-8
+et_EE.UTF-8
+eu_ES.UTF-8
+eu_FR.UTF-8
+fa_IR
+ff_SN
+fi_FI.UTF-8
+fil_PH
+fo_FO.UTF-8
+fr_BE.UTF-8
+fr_CA.UTF-8
+fr_CH.UTF-8
+fr_FR.UTF-8
+fr_LU.UTF-8
+fur_IT
+fy_NL
+fy_DE
+ga_IE.UTF-8
+gd_GB.UTF-8
+gez_ER
+gez_ER@abegede
+gez_ET
+gez_ET@abegede
+gl_ES.UTF-8
+gu_IN
+gv_GB.UTF-8
+ha_NG
+hak_TW
+he_IL.UTF-8
+hi_IN
+hif_FJ
+hne_IN
+hr_HR.UTF-8
+hsb_DE.UTF-8
+ht_HT
+hu_HU.UTF-8
+hy_AM
+ia_FR
+id_ID.UTF-8
+ig_NG
+ik_CA
+is_IS.UTF-8
+it_CH.UTF-8
+it_IT.UTF-8
+iu_CA
+ja_JP.UTF-8
+ka_GE.UTF-8
+kab_DZ
+kk_KZ.UTF-8
+kl_GL.UTF-8
+km_KH
+kn_IN
+ko_KR.UTF-8
+kok_IN
+ks_IN
+ks_IN@devanagari
+ku_TR.UTF-8
+kw_GB.UTF-8
+ky_KG
+lb_LU
+lg_UG.UTF-8
+li_BE
+li_NL
+lij_IT
+ln_CD
+lo_LA
+lt_LT.UTF-8
+lv_LV.UTF-8
+lzh_TW
+mag_IN
+mai_IN
+mai_NP
+mfe_MU
+mg_MG.UTF-8
+mhr_RU
+mi_NZ.UTF-8
+miq_NI
+mjw_IN
+mk_MK.UTF-8
+ml_IN
+mn_MN
+mni_IN
+mnw_MM
+mr_IN
+ms_MY.UTF-8
+mt_MT.UTF-8
+my_MM
+nan_TW
+nan_TW@latin
+nb_NO.UTF-8
+nds_DE
+nds_NL
+ne_NP
+nhn_MX
+niu_NU
+niu_NZ
+nl_AW
+nl_BE.UTF-8
+nl_NL.UTF-8
+nn_NO.UTF-8
+nr_ZA
+nso_ZA
+oc_FR.UTF-8
+om_ET
+om_KE.UTF-8
+or_IN
+os_RU
+pa_IN
+pa_PK
+pap_AW
+pap_CW
+pl_PL.UTF-8
+ps_AF
+pt_BR.UTF-8
+pt_PT.UTF-8
+quz_PE
+raj_IN
+ro_RO.UTF-8
+ru_RU.UTF-8
+ru_UA.UTF-8
+rw_RW
+sa_IN
+sah_RU
+sat_IN
+sc_IT
+sd_IN
+sd_IN@devanagari
+sd_PK
+se_NO
+sgs_LT
+shn_MM
+shs_CA
+si_LK
+sid_ET
+sk_SK.UTF-8
+sl_SI.UTF-8
+sm_WS
+so_DJ.UTF-8
+so_ET
+so_KE.UTF-8
+so_SO.UTF-8
+sq_AL.UTF-8
+sq_MK
+sr_ME
+sr_RS
+sr_RS@latin
+ss_ZA
+st_ZA.UTF-8
+sv_FI.UTF-8
+sv_SE.UTF-8
+sw_KE
+sw_TZ
+szl_PL
+ta_IN
+ta_LK
+tcy_IN.UTF-8
+te_IN
+tg_TJ.UTF-8
+th_TH.UTF-8
+the_NP
+ti_ER
+ti_ET
+tig_ER
+tk_TM
+tl_PH.UTF-8
+tn_ZA
+to_TO
+tpi_PG
+tr_CY.UTF-8
+tr_TR.UTF-8
+ts_ZA
+tt_RU
+tt_RU@iqtelif
+ug_CN
+ug_CN@latin
+uk_UA.UTF-8
+unm_US
+ur_IN
+ur_PK
+uz_UZ.UTF-8
+uz_UZ@cyrillic
+ve_ZA
+vi_VN
+wa_BE.UTF-8
+wae_CH
+wal_ET
+wo_SN
+xh_ZA.UTF-8
+yi_US.UTF-8
+yo_NG
+yue_HK
+yuw_PG
+zh_CN.UTF-8
+zh_HK.UTF-8
+zh_SG.UTF-8
+zh_TW.UTF-8
+zu_ZA.UTF-8