diff --git a/src/main/java/module-info.java b/src/main/java/module-info.java
index 040717bf9072..c6ed2d0cad3a 100644
--- a/src/main/java/module-info.java
+++ b/src/main/java/module-info.java
@@ -155,7 +155,7 @@
 
     // region: Lucene
     /**
-     * In case the version is updated, please also adapt {@link org.jabref.model.search.SearchFieldConstants#VERSION} to the newly used version.
+     * In case the version is updated, please also increment {@link org.jabref.model.search.SearchFieldConstants#VERSION} to trigger reindexing.
      */
     uses org.apache.lucene.codecs.lucene99.Lucene99Codec;
     requires org.apache.lucene.analysis.common;
diff --git a/src/main/java/org/jabref/gui/LibraryTab.java b/src/main/java/org/jabref/gui/LibraryTab.java
index ecfaa501e70d..0542c7023fee 100644
--- a/src/main/java/org/jabref/gui/LibraryTab.java
+++ b/src/main/java/org/jabref/gui/LibraryTab.java
@@ -858,7 +858,9 @@ private void onClosed(Event event) {
             LOGGER.error("Problem when closing directory monitor", e);
         }
         try {
-            luceneManager.close();
+            if (luceneManager != null) {
+                luceneManager.close();
+            }
         } catch (RuntimeException e) {
             LOGGER.error("Problem when closing lucene indexer", e);
         }
diff --git a/src/main/java/org/jabref/model/search/Analyzer/LatexAwareNGramAnalyzer.java b/src/main/java/org/jabref/model/search/Analyzer/LatexAwareNGramAnalyzer.java
index f1f9ddabc3f7..aafb993390d3 100644
--- a/src/main/java/org/jabref/model/search/Analyzer/LatexAwareNGramAnalyzer.java
+++ b/src/main/java/org/jabref/model/search/Analyzer/LatexAwareNGramAnalyzer.java
@@ -26,7 +26,7 @@ protected TokenStreamComponents createComponents(String fieldName) {
         result = new StopFilter(result, EnglishAnalyzer.ENGLISH_STOP_WORDS_SET);
         result = new ASCIIFoldingFilter(result);
         result = new LowerCaseFilter(result);
-         result = new EdgeNGramTokenFilter(result, minGram, maxGram, true);
+        result = new EdgeNGramTokenFilter(result, minGram, maxGram, true);
         return new TokenStreamComponents(source, result);
     }
 }
diff --git a/src/main/java/org/jabref/model/search/SearchFieldConstants.java b/src/main/java/org/jabref/model/search/SearchFieldConstants.java
index 8becbeb18517..12aa58576da2 100644
--- a/src/main/java/org/jabref/model/search/SearchFieldConstants.java
+++ b/src/main/java/org/jabref/model/search/SearchFieldConstants.java
@@ -9,8 +9,14 @@
 import org.apache.lucene.analysis.en.EnglishAnalyzer;
 
 public enum SearchFieldConstants {
-
-    VERSION("99"),
+    /**
+     * Version number for the search index.
+     * Increment when:
+     * 1. Index changes require reindexing (e.g., new/removed/renamed fields, analyzer changes)
+     * 2. Lucene codec changes (see module-info.java Lucene section)
+     * Incrementing triggers reindexing.
+     */
+    VERSION("1"),
     DEFAULT_FIELD("any"),
     ENTRY_ID("id"),
     ENTRY_TYPE("entrytype"),