Add selection of 'All Entries' group on start-up

CHANGELOG.md

@@ -51,6 +51,7 @@ inserting new citations in a OpenOffic/LibreOffice document. [#6957](https://git
 - We fixed an issue with the python script used by browser plugins that failed to locate JabRef if not installed in its default location. [#6963](https://github.com/JabRef/jabref/pull/6963/files)
 - We fixed an issue where identity column header had incorrect foreground color in the  Dark theme. [#6796](https://github.com/JabRef/jabref/issues/6796)
 - We fixed an issue where clicking on Collapse All button in the Search for Unlinked Local Files expanded the directory structure erroneously [#6848](https://github.com/JabRef/jabref/issues/6848)
+- We fixed an issue where the JabRef GUI does not highlight the "All entries" group on start-up [#6691](https://github.com/JabRef/jabref/issues/6691)
 
 ### Removed
 

src/main/java/org/jabref/gui/groups/GroupTreeViewModel.java

@@ -1,5 +1,6 @@
 package org.jabref.gui.groups;
 
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Objects;
@@ -129,6 +130,9 @@ private void onActiveDatabaseChanged(Optional<BibDatabaseContext> newDatabase) {
                     .orElse(GroupNodeViewModel.getAllEntriesGroup(newDatabase.get(), stateManager, taskExecutor, localDragboard, preferences));
 
             rootGroup.setValue(newRoot);
+            if (stateManager.getSelectedGroup(newDatabase.get()).isEmpty()) {
+                stateManager.setSelectedGroups(newDatabase.get(), Collections.singletonList(newRoot.getGroupNode()));
+            }
             selectedGroups.setAll(
                     stateManager.getSelectedGroup(newDatabase.get()).stream()
                                 .map(selectedGroup -> new GroupNodeViewModel(newDatabase.get(), stateManager, taskExecutor, selectedGroup, localDragboard, preferences))

src/test/java/org/jabref/gui/groups/GroupTreeViewModelTest.java

@@ -43,6 +43,11 @@ void rootGroupIsAllEntriesByDefault() throws Exception {
         assertEquals(new GroupNodeViewModel(databaseContext, stateManager, taskExecutor, allEntriesGroup, new CustomLocalDragboard(), mock(PreferencesService.class)), groupTree.rootGroupProperty().getValue());
     }
 
+    @Test
+    void rootGroupIsSelectedByDefault() {
+        assertEquals(groupTree.rootGroupProperty().get().getGroupNode(), stateManager.getSelectedGroup(databaseContext).get(0));
+    }
+
     @Test
     void explicitGroupsAreRemovedFromEntriesOnDelete() {
         ExplicitGroup group = new ExplicitGroup("group", GroupHierarchyType.INDEPENDENT, ',');