diff --git a/Event/xAOD/xAODBTaggingAthenaPool/test/xAODBTaggingAthenaPool_21.0.79_test.py b/Event/xAOD/xAODBTaggingAthenaPool/test/xAODBTaggingAthenaPool_21.0.79_test.py
index 1586a515aae1dfa369c3250a60d6e65c6f36b43e..5dbe62db82c8ddfa0cc6bb6cb32e7a4ea4782882 100755
--- a/Event/xAOD/xAODBTaggingAthenaPool/test/xAODBTaggingAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODBTaggingAthenaPool/test/xAODBTaggingAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::BTaggingAuxContainer_v1
diff --git a/Event/xAOD/xAODCaloEventAthenaPool/CMakeLists.txt b/Event/xAOD/xAODCaloEventAthenaPool/CMakeLists.txt
index c9651a3619579e8522eb4e3bffe3dda5f2f9d5c2..5901acedf5bb5eed03cd14439426dc95880890f7 100644
--- a/Event/xAOD/xAODCaloEventAthenaPool/CMakeLists.txt
+++ b/Event/xAOD/xAODCaloEventAthenaPool/CMakeLists.txt
@@ -26,6 +26,12 @@ atlas_add_poolcnv_library( xAODCaloEventAthenaPoolPoolCnv
 atlas_install_joboptions( share/*.py )
 atlas_install_scripts( test/*.py POST_BUILD_CMD ${ATLAS_FLAKE8} )
 
+# In AthAnalysis xAOD::CaloCluster doesn't know about its CaloCell link. Which
+# makes the converter tests fail in that project...
+if( XAOD_ANALYSIS )
+   return()
+endif()
+
 # Set up (a) test(s) for the converter(s):
 find_package( AthenaPoolUtilitiesTest )
 
diff --git a/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_20.1.7.2_test.py
index 2e4154e6f8708821b2188c28e720b72c0c577b3a..5d39af506619fc6d8ce975fce0573895d0fb1c9e 100755
--- a/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #xAOD::CaloCluster
diff --git a/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_21.0.79_test.py b/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_21.0.79_test.py
index 2f7e4720ba467a38b793b5339e120cf7628f438f..2bd06fe7ecc13fcc98159cee0af5fd6fb1485227 100755
--- a/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODCaloEventAthenaPool/test/xAODCaloEventAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::CaloCluster
diff --git a/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_20.1.7.2_test.py
index 1a002c879aa1b5c3a44f061e5c658886408ebfce..56410043ddac05499e1132e590cdd184d51c1c62 100755
--- a/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #xAOD::ElectronAuxContainer
diff --git a/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_21.0.79_test.py b/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_21.0.79_test.py
index 6d1e56c27f7471cd176adda7111c1885365f6cb6..7321ff27d18312e80adbb073599a9e7982370122 100755
--- a/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODEgammaAthenaPool/test/xAODEgammaAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::ElectronAuxContainer_v3
diff --git a/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_20.7.2.2_test.py b/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_20.7.2.2_test.py
index ce7b77031206319da6d9fbfac3ad138f3b9bfc8f..3f28b32a09b6eb0318d1eb9df392fe47d1e4a089 100755
--- a/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_20.7.2.2_test.py
+++ b/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_20.7.2.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.7.2.2/AOD-20.7.2.2-full.pool.root'
     keys = [
         #xAOD::JetTrigAuxContainer_v2
diff --git a/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_21.0.79_test.py b/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_21.0.79_test.py
index 98994b79d3bd046ad8f3c17035d254ff0c99656e..8fe437f40e5a319865d797249eb492532a4b4b44 100755
--- a/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODJetAthenaPool/test/xAODJetAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::JetTrigAuxContainer_v2
diff --git a/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_20.1.7.2_test.py
index d933826d07db2910580b61f48f585389c6d06673..eb457c8a619c26a9a2ec662217378adb5819e042 100755
--- a/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #xAOD::MissingETAssociationMap
diff --git a/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_21.0.79_test.py b/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_21.0.79_test.py
index f43f7b83428de67aec5ec387c0e06b53167e21e6..3b2e3aad5648b4586d8974274ee11be4fbbd114a 100755
--- a/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODMissingETAthenaPool/test/xAODMissingETAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::MissingETAuxAssociationMap_v2
diff --git a/Event/xAOD/xAODMuonAthenaPool/CMakeLists.txt b/Event/xAOD/xAODMuonAthenaPool/CMakeLists.txt
index 353c84b01d8fb00e4c460f3258bff8c38329a5e3..9c8f759fcd66f1ecb68f82e564090c1b8a97667a 100644
--- a/Event/xAOD/xAODMuonAthenaPool/CMakeLists.txt
+++ b/Event/xAOD/xAODMuonAthenaPool/CMakeLists.txt
@@ -25,6 +25,12 @@ atlas_add_poolcnv_library( xAODMuonAthenaPoolPoolCnv
 atlas_install_joboptions( share/*.py )
 atlas_install_scripts( test/*.py POST_BUILD_CMD ${ATLAS_FLAKE8} )
 
+# In AthAnalysis xAOD::Muon doesn't know about its MuonSegment link. Which
+# makes the converter tests fail in that project...
+if( XAOD_ANALYSIS )
+   return()
+endif()
+
 # Set up (a) test(s) for the converter(s):
 find_package( AthenaPoolUtilitiesTest )
 
diff --git a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.1.7.2_test.py
index 0b989d4954b64599f82cfc380e395dec528b5aa1..d2748c20b966e3334f5667c2e9e02a810dfa28bf 100755
--- a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #Muons...
diff --git a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.2.2_test.py b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.2.2_test.py
index cc7882cc2a83d372fcf454278d7c798728de93bd..b732ce2c7a97d6736d7dd299ee0d3e0c708b8c0c 100755
--- a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.2.2_test.py
+++ b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.2.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.7.2.2/AOD-20.7.2.2-full.pool.root'
     keys = [
         #xAOD::MuonAuxContainer_v2
diff --git a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.9.9_test.py b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.9.9_test.py
index 35210998e699087a468ddd8f5b06a1a7e6f0605d..784da1fbdb695fc06067b96c1094a6a6eabdf75e 100755
--- a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.9.9_test.py
+++ b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_20.7.9.9_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.7.9.9/AOD-20.7.9.9-full.pool.root'
     keys = [
         #xAOD::MuonAuxContainer_v4
diff --git a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_21.0.79_test.py b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_21.0.79_test.py
index 742918ebc9beb69965302fed65419742b3a9e1b3..95cf862fec0af841db18f523c5c55e2eee7f5221 100755
--- a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::MuonAuxContainer_v4
diff --git a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_master-20190911_test.py b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_master-20190911_test.py
index 70a4d1ae5123035dff28f3f43a7a6ba8a2ec629b..81a183add39e9ac01f99d7b86489a3e628c10250 100755
--- a/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_master-20190911_test.py
+++ b/Event/xAOD/xAODMuonAthenaPool/test/xAODMuonAthenaPool_master-20190911_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-master-20190911/AOD-master-20190911-full.pool.root'
     keys = [
         #xAOD::MuonAuxContainer_v5
diff --git a/Event/xAOD/xAODPFlowAthenaPool/test/xAODPFlowAthenaPool_21.0.79_test.py b/Event/xAOD/xAODPFlowAthenaPool/test/xAODPFlowAthenaPool_21.0.79_test.py
index a3d3f81fa19f93da8190294cac437f14f96a7c72..3a2042e8dd8f47f5084c05dfd978ad21f7813f22 100755
--- a/Event/xAOD/xAODPFlowAthenaPool/test/xAODPFlowAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODPFlowAthenaPool/test/xAODPFlowAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::PFOAuxContainer_v1
diff --git a/Event/xAOD/xAODParticleEventAthenaPool/test/xAODParticleAthenaPool_21.0.79_test.py b/Event/xAOD/xAODParticleEventAthenaPool/test/xAODParticleAthenaPool_21.0.79_test.py
index eaaf9cc1d31ca0478855941277bf98dc91b017ba..67fad4ce1b7c25a472fad730927dc34b3ac552f1 100755
--- a/Event/xAOD/xAODParticleEventAthenaPool/test/xAODParticleAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODParticleEventAthenaPool/test/xAODParticleAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::ParticleAuxContainer_v1
diff --git a/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.1.7.2_test.py
index 8b2bbfeb04767ef744464ef3bebf111a1ac48e3d..32ed933c6642dc476145dc12d77e5e34d71af5bc 100755
--- a/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #xAOD::TauJetAuxContainer
diff --git a/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.7.2.2_test.py b/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.7.2.2_test.py
index dae8e87fa0d6f06e7c2528da2517d9bd6679a3c8..1a7a0f7667c175cf98233b96c1c053d31a868a67 100755
--- a/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.7.2.2_test.py
+++ b/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_20.7.2.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.7.2.2/AOD-20.7.2.2-full.pool.root'
     keys = [
         #xAOD::DiTauJetAuxContainer_v1
diff --git a/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_21.0.79_test.py b/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_21.0.79_test.py
index a65bbb30733d1edce03179bc48e1a596ec69df24..2248314778861a709e01045f615b914b5e3b07dd 100755
--- a/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODTauAthenaPool/test/xAODTauAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::DiTauJetAuxContainer_v1
diff --git a/Event/xAOD/xAODTrackingAthenaPool/CMakeLists.txt b/Event/xAOD/xAODTrackingAthenaPool/CMakeLists.txt
index dd31c801fa8220ba98d3f937e6fb01e77865c414..de3f338d3359b554551fecc25f01eeaf79c49330 100644
--- a/Event/xAOD/xAODTrackingAthenaPool/CMakeLists.txt
+++ b/Event/xAOD/xAODTrackingAthenaPool/CMakeLists.txt
@@ -37,6 +37,12 @@ atlas_add_poolcnv_library( xAODTrackingAthenaPoolPoolCnv
 atlas_install_joboptions( share/*.py )
 atlas_install_scripts( test/*.py POST_BUILD_CMD ${ATLAS_FLAKE8} )
 
+# In AthAnalysis xAOD::TrackParticle doesn't know about its Trk::Track link.
+# Which makes the converter tests fail in that project...
+if( XAOD_ANALYSIS )
+   return()
+endif()
+
 # Set up (a) test(s) for the converter(s):
 find_package( AthenaPoolUtilitiesTest )
 
diff --git a/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_20.0.0.3_test.py b/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_20.0.0.3_test.py
index 91c4eb7011bba12f2597d127a9625130bf099da1..4c854f1614d086f8e36eeba9fb69a64a1db9be6c 100755
--- a/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_20.0.0.3_test.py
+++ b/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_20.0.0.3_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.0.0.3/AOD-20.0.0.3-full.pool.root'
     keys = [
         #xAOD::TrigCaloClusterAuxContainer_v1
diff --git a/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_21.0.79_test.py b/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_21.0.79_test.py
index 3687da81dbeed9ba870d4aa3505fe0226687c84c..5596c4ad8c9cd18507318f2dd7044db0aad27a1a 100755
--- a/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODTrigCaloAthenaPool/test/xAODTrigCaloAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::CaloClusterTrigAuxContainer_v1
diff --git a/Event/xAOD/xAODTrigEgammaAthenaPool/test/xAODTrigEgammaAthenaPool_21.0.79_test.py b/Event/xAOD/xAODTrigEgammaAthenaPool/test/xAODTrigEgammaAthenaPool_21.0.79_test.py
index 7564d3e52771a3eec6b32a62351e4ba3c8e1c4a5..8e88594ce85d119ea648b1ef671e4e0ad9b19dff 100755
--- a/Event/xAOD/xAODTrigEgammaAthenaPool/test/xAODTrigEgammaAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODTrigEgammaAthenaPool/test/xAODTrigEgammaAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::ElectronTrigAuxContainer_v1
diff --git a/Event/xAOD/xAODTrigMissingETAthenaPool/test/xAODTrigMissingETAthenaPool_21.0.79_test.py b/Event/xAOD/xAODTrigMissingETAthenaPool/test/xAODTrigMissingETAthenaPool_21.0.79_test.py
index 658ee021b7aef76e392f9f6050dd98cff9961714..05e7b59a195c2a4df7ec75c9ddfd6797593ae2d6 100755
--- a/Event/xAOD/xAODTrigMissingETAthenaPool/test/xAODTrigMissingETAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODTrigMissingETAthenaPool/test/xAODTrigMissingETAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::TrigMissingETAuxContainer_v1
diff --git a/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_20.1.7.2_test.py
index a728cd13361608125123ea102fca4c6f2847a673..31b049dbc6e70b224fda458efc04875133e45ce5 100755
--- a/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #xAOD::L2CombinedMuonAuxContainer
diff --git a/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_21.0.79_test.py b/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_21.0.79_test.py
index 0e157b4bf1af1bdd0e924929872bbc56c339fb06..296f9eeb42912dce21501d4d6ffa8f35f6a6db89 100755
--- a/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODTrigMuonAthenaPool/test/xAODTrigMuonAthenaPool_21.0.79_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::L2CombinedMuonAuxContainer_v1
diff --git a/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_20.1.7.2_test.py b/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_20.1.7.2_test.py
index 476752fdba8e029a9290089ed6814087fe37a982..67e184e1ae59c911499c048078135c2d8be51bf9 100755
--- a/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_20.1.7.2_test.py
+++ b/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_20.1.7.2_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-20.1.7.2/AOD-20.1.7.2-full.pool.root'
     keys = [
         #EmTauRoI
diff --git a/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_master-20190911_test.py b/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_master-20190911_test.py
index 7f2c7e0ceb2d2277624fbc47753adcfe88e384a2..ff34d84ada5681786e6af3d93e892623ee015ae6 100755
--- a/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_master-20190911_test.py
+++ b/Event/xAOD/xAODTriggerAthenaPool/test/xAODTriggerAthenaPool_master-20190911_test.py
@@ -3,10 +3,14 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
     infile = 'aod/AOD-master-20190911/AOD-master-20190911-full.pool.root'
     keys = [
         #EmTauRoI_v2
diff --git a/Event/xAOD/xAODTruthAthenaPool/test/xAODTruthAthenaPool_21.0.79_test.py b/Event/xAOD/xAODTruthAthenaPool/test/xAODTruthAthenaPool_21.0.79_test.py
index 0f6816c00729dbce9fe0819189ab505c2c4aeb88..22c15e5c3052972d52c8f0ce758862c46a45dc97 100755
--- a/Event/xAOD/xAODTruthAthenaPool/test/xAODTruthAthenaPool_21.0.79_test.py
+++ b/Event/xAOD/xAODTruthAthenaPool/test/xAODTruthAthenaPool_21.0.79_test.py
@@ -3,11 +3,15 @@
 Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 """
 
+import ROOT
 from AthenaPoolUtilities.TPCnvTestConfig import TPCnvTest
 
 if __name__ == "__main__":
-    infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
 
+    # Force-load some dictionaries. Needed to work around ROOT-10940.
+    ROOT.xAOD.CaloCluster()
+
+    infile = 'aod/AOD-21.0.79/AOD-21.0.79-full.pool.root'
     keys = [
         #xAOD::TruthEventAuxContainer_v1
         'TruthEvents',
@@ -19,4 +23,4 @@ if __name__ == "__main__":
         'TruthVertices',
     ]
 
-    TPCnvTest(infile, keys)#, useGeoModelSvc=True, doLAr=True, doTile=True)
+    TPCnvTest(infile, keys)