diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/query/QueryStringValue.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/query/QueryStringValue.kt
index 8f83beface..1490bff6a8 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/query/QueryStringValue.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/query/QueryStringValue.kt
@@ -19,14 +19,17 @@ package org.matrix.android.sdk.api.query
 /**
  * Basic query language. All these cases are mutually exclusive.
  */
-sealed class QueryStringValue {
-    object NoCondition : QueryStringValue()
-    object IsNull : QueryStringValue()
-    object IsNotNull : QueryStringValue()
-    object IsEmpty : QueryStringValue()
-    object IsNotEmpty : QueryStringValue()
-    data class Equals(val string: String, val case: Case = Case.SENSITIVE) : QueryStringValue()
-    data class Contains(val string: String, val case: Case = Case.SENSITIVE) : QueryStringValue()
+sealed interface QueryStringValue {
+    sealed interface ContentQueryStringValue : QueryStringValue
+
+    object NoCondition : QueryStringValue
+    object IsNull : QueryStringValue
+    object IsNotNull : QueryStringValue
+    object IsEmpty : QueryStringValue
+    object IsNotEmpty : QueryStringValue
+
+    data class Equals(val string: String, val case: Case = Case.SENSITIVE) : ContentQueryStringValue
+    data class Contains(val string: String, val case: Case = Case.SENSITIVE) : ContentQueryStringValue
 
     enum class Case {
         SENSITIVE,
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/query/QueryStringValueProcessor.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/query/QueryStringValueProcessor.kt
index fd33682231..b3f207e7f3 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/query/QueryStringValueProcessor.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/query/QueryStringValueProcessor.kt
@@ -20,19 +20,24 @@ import io.realm.Case
 import io.realm.RealmObject
 import io.realm.RealmQuery
 import org.matrix.android.sdk.api.query.QueryStringValue
+import org.matrix.android.sdk.api.query.QueryStringValue.ContentQueryStringValue
 import timber.log.Timber
 
 fun <T : RealmObject> RealmQuery<T>.process(field: String, queryStringValue: QueryStringValue): RealmQuery<T> {
-    when (queryStringValue) {
-        is QueryStringValue.NoCondition -> Timber.v("No condition to process")
+    return when (queryStringValue) {
+        is QueryStringValue.NoCondition -> {
+            Timber.v("No condition to process")
+            this
+        }
         is QueryStringValue.IsNotNull   -> isNotNull(field)
         is QueryStringValue.IsNull      -> isNull(field)
         is QueryStringValue.IsEmpty     -> isEmpty(field)
         is QueryStringValue.IsNotEmpty  -> isNotEmpty(field)
-        is QueryStringValue.Equals      -> equalTo(field, queryStringValue.string, queryStringValue.case.toRealmCase())
-        is QueryStringValue.Contains    -> contains(field, queryStringValue.string, queryStringValue.case.toRealmCase())
+        is ContentQueryStringValue      -> when (queryStringValue) {
+            is QueryStringValue.Equals   -> equalTo(field, queryStringValue.string, queryStringValue.case.toRealmCase())
+            is QueryStringValue.Contains -> contains(field, queryStringValue.string, queryStringValue.case.toRealmCase())
+        }
     }
-    return this
 }
 
 private fun QueryStringValue.Case.toRealmCase(): Case {