diff --git a/backend/src/main/java/com/bakdata/conquery/models/datasets/PreviewConfig.java b/backend/src/main/java/com/bakdata/conquery/models/datasets/PreviewConfig.java
index a3639bbee3..f57ee2c03e 100644
--- a/backend/src/main/java/com/bakdata/conquery/models/datasets/PreviewConfig.java
+++ b/backend/src/main/java/com/bakdata/conquery/models/datasets/PreviewConfig.java
@@ -117,14 +117,14 @@ public record TimeStratifiedSelects(@NotNull String label, String description, @
 	@JsonIgnore
 	public boolean isSelectsUnique() {
 		return timeStratifiedSelects.stream().map(TimeStratifiedSelects::selects).flatMap(Collection::stream).map(InfoCardSelect::select).distinct().count()
-			   == timeStratifiedSelects.stream().map(TimeStratifiedSelects::selects).flatMap(Collection::stream).count();
+			   == timeStratifiedSelects.stream().map(TimeStratifiedSelects::selects).mapToLong(Collection::size).sum();
 	}
 
 	@ValidationMethod(message = "Labels must be unique.")
 	@JsonIgnore
 	public boolean isLabelsUnique() {
 		return timeStratifiedSelects.stream().map(TimeStratifiedSelects::selects).flatMap(Collection::stream).map(InfoCardSelect::label).distinct().count()
-			   == timeStratifiedSelects.stream().map(TimeStratifiedSelects::selects).flatMap(Collection::stream).count();
+			   == timeStratifiedSelects.stream().map(TimeStratifiedSelects::selects).mapToLong(Collection::size).sum();
 	}
 
 	@JsonIgnore
@@ -178,7 +178,7 @@ public String resolveSelectLabel(SelectResultInfo info) {
 	public List<Select> getSelects() {
 		return getInfoCardSelects().stream()
 								   .map(InfoCardSelect::select)
-								   .map(SelectId::<Select>resolve)
+								   .map(SelectId::resolve)
 								   .collect(Collectors.toList());
 	}
 
@@ -200,10 +200,10 @@ public ConceptId resolveSearchConcept() {
 
 
 		return searchFilters.stream()
-							.map(FilterId::<Filter<?>>resolve)
+							.map(FilterId::resolve)
 							.map(filter -> filter.getConnector().getConcept())
 							.distinct()
 							.map(Concept::getId)
-							.collect(MoreCollectors.onlyElement());
+							.collect(MoreCollectors.toOptional()).orElse(null);
 	}
 }
diff --git a/cypress/e2e/frontend/test_1_runQuery.cy.js b/cypress/e2e/frontend/test_1_runQuery.cy.js
index d20a199c3e..50e7f69f37 100644
--- a/cypress/e2e/frontend/test_1_runQuery.cy.js
+++ b/cypress/e2e/frontend/test_1_runQuery.cy.js
@@ -12,7 +12,7 @@ describe("Run query", () => {
     visitWithToken(USER_TOKEN_WITH_PERMISSIONS);
   });
 
-  it("Can execute query and see it in the queries tab", () => {
+  it("Can execute query, see it in the queries tab and delete it", () => {
     cy.get('[data-test-id="right-pane-container"] >div:visible').as("queryEditor");
 
     // Drag concept to editor
@@ -40,18 +40,16 @@ describe("Run query", () => {
     cy.get("@queryEditor").find('[data-test-id="query-runner-button"]').click();
 
     cy.get("@queryEditor").contains("Ergebnisse");
-  });
 
-  it("Can see the executed query in the queries tab", () => {
+    // Lookup executed query in the previous queries tab
     cy.get('[data-test-id="left-pane"]').contains("Anfragen").click();
 
     cy.get('[data-test-id="left-pane-container"]').as("leftPaneContainer");
 
     cy.get("@leftPaneContainer").contains("Ergebnisse");
     cy.get("@leftPaneContainer").contains("Concept1");
-  });
 
-  it("Can delete the query", () => {
+    // Delete the Query
     cy.get('[data-test-id="left-pane"]').contains("Anfragen").click();
 
     cy.get('[data-test-id="left-pane-container"]').as("leftPaneContainer");
@@ -60,6 +58,8 @@ describe("Run query", () => {
     
     cy.get('@executionList').find('[data-test-id="project-item-delete-button"]').click();
     cy.get('@executionList').contains('Anfrage jetzt löschen').click();
+
+    cy.get('@leftPaneContainer').contains('Keine Anfragen / Formulare gefunden')
   });
 });
 
diff --git a/frontend/src/js/previous-queries/list/DeleteProjectItemButton.tsx b/frontend/src/js/previous-queries/list/DeleteProjectItemButton.tsx
index 7ea16ca053..05b3a56f9c 100644
--- a/frontend/src/js/previous-queries/list/DeleteProjectItemButton.tsx
+++ b/frontend/src/js/previous-queries/list/DeleteProjectItemButton.tsx
@@ -41,6 +41,7 @@ export const DeleteProjectItemButton = ({ item }: { item: ProjectItemT }) => {
         <IconButton
           icon={faTimes}
           bare
+          title="delete"
           data-test-id="project-item-delete-button"
         />
       </WithTooltip>
diff --git a/frontend/src/js/previous-queries/list/ProjectItem.tsx b/frontend/src/js/previous-queries/list/ProjectItem.tsx
index 700d15cde6..10c578011e 100644
--- a/frontend/src/js/previous-queries/list/ProjectItem.tsx
+++ b/frontend/src/js/previous-queries/list/ProjectItem.tsx
@@ -276,6 +276,8 @@ const ProjectItem = forwardRef<
                 <IconButton
                   icon={isShared ? faUser : faUserRegular}
                   bare
+                  title="share"
+                  data-test-id="share"
                   onClick={onIndicateShare}
                 />
               </WithTooltip>