diff --git a/packages/ckeditor5-core/tests/editor/utils/editorusagedata.js b/packages/ckeditor5-core/tests/editor/utils/editorusagedata.js
index 590b7a79b4d..18e3a675ff9 100644
--- a/packages/ckeditor5-core/tests/editor/utils/editorusagedata.js
+++ b/packages/ckeditor5-core/tests/editor/utils/editorusagedata.js
@@ -192,7 +192,7 @@ describe( 'getEditorUsageData()', () => {
 
 			for ( const [ flag, osName ] of os ) {
 				it( `should detect ${ osName } OS`, async () => {
-					sinon.stub( env, flag ).value( true );
+					mockFlag( flag );
 
 					editor = await ClassicTestEditor.create( domElement, {} );
 
@@ -201,6 +201,12 @@ describe( 'getEditorUsageData()', () => {
 					} );
 				} );
 			}
+
+			function mockFlag( mockFlag ) {
+				for ( const [ flag ] of os ) {
+					sinon.stub( env, flag ).value( flag === mockFlag );
+				}
+			}
 		} );
 
 		describe( 'browser', () => {
@@ -212,11 +218,7 @@ describe( 'getEditorUsageData()', () => {
 
 			for ( const [ flag, browser ] of browsers ) {
 				it( `should detect ${ browser } browser`, async () => {
-					sinon.stub( env, flag ).value( true );
-
-					if ( flag !== 'isBlink' ) {
-						sinon.stub( env, 'isBlink' ).value( false );
-					}
+					mockFlag( flag );
 
 					editor = await ClassicTestEditor.create( domElement, {} );
 
@@ -225,6 +227,12 @@ describe( 'getEditorUsageData()', () => {
 					} );
 				} );
 			}
+
+			function mockFlag( mockFlag ) {
+				for ( const [ flag ] of browsers ) {
+					sinon.stub( env, flag ).value( flag === mockFlag );
+				}
+			}
 		} );
 	} );