diff --git a/configure.json b/configure.json
index 726d151c75a7d91f4427c02c54a99939cf2ea0e3..f2cd78343703b8a2e8f94834c2f37f2978e57fd3 100644
--- a/configure.json
+++ b/configure.json
@@ -444,6 +444,11 @@
             "label": "UI Delegates",
             "output": [ "privateFeature" ]
         },
+        "testsupport": {
+            "label": "Test Support",
+            "autoDetect": "config.private_tests || call.isTestsInBuildParts",
+            "output": [ "privateFeature" ]
+        },
         "webrtc": {
             "label": "WebRTC",
             "purpose": "Provides WebRTC support.",
diff --git a/configure.pri b/configure.pri
index c88d4964be22f7e93d129ce8509fb9a7116c22fb..0b6f9fd1b2e739f89d77ea4edd1865f0af59d167 100644
--- a/configure.pri
+++ b/configure.pri
@@ -245,3 +245,8 @@ defineTest(isSanitizerLinuxClangVersionSupported) {
   qtLog("Using Clang version $${QT_CLANG_MAJOR_VERSION}.$${QT_CLANG_MINOR_VERSION}, but at least Clang version 3.7 is required to build a sanitizer-enabled Qt WebEngine.")
   return(false)
 }
+
+defineReplace(qtConfFunc_isTestsInBuildParts) {
+    contains(QT_BUILD_PARTS, tests): return(true)
+    return(false)
+}
diff --git a/mkspecs/features/functions.prf b/mkspecs/features/functions.prf
index cdb826d98c9222413baae47c82fdb4af86124641..0074a27b009288af31a12e37ff474e27291d4f40 100644
--- a/mkspecs/features/functions.prf
+++ b/mkspecs/features/functions.prf
@@ -116,18 +116,6 @@ defineReplace(gnOS) {
     return(unknown)
 }
 
-defineTest(isDeveloperBuild) {
-    qtConfig(private_tests): return(true) # enabled for developer-build
-    return(false)
-}
-
-defineTest(isQMLTestSupportApiEnabled) {
-    isDeveloperBuild(): return(true)
-    contains(QT_BUILD_PARTS, tests): return(true)
-    contains(WEBENGINE_CONFIG, testsupport): return(true)
-    return(false)
-}
-
 defineTest(skipBuild) {
     skipBuildReason = "$$skipBuildReason $${EOL}$$1"
     export(skipBuildReason)
diff --git a/src/src.pro b/src/src.pro
index d994fc0e9b5357ad40c94eb037b29659a00eae38..fabead2a057dba58eda3032c45c8cc3f9cf8e24b 100644
--- a/src/src.pro
+++ b/src/src.pro
@@ -26,7 +26,7 @@ use?(spellchecker):!use?(native_spellchecker):!cross_compile {
     qwebengine_convert_dict.depends = core
 }
 
-isQMLTestSupportApiEnabled() {
+qtConfig(testsupport) {
     webengine_testsupport_plugin.subdir = webengine/plugin/testsupport
     webengine_testsupport_plugin.target = sub-webengine-testsupport-plugin
     webengine_testsupport_plugin.depends = webengine
diff --git a/src/webengine/webengine.pro b/src/webengine/webengine.pro
index f4bc65edba0cb312ffc1bea02cc31a4d1b504f38..ac2727580f55bb85ac7062aba6fdb4ceaed7e55f 100644
--- a/src/webengine/webengine.pro
+++ b/src/webengine/webengine.pro
@@ -1,3 +1,6 @@
+include($$QTWEBENGINE_OUT_ROOT/qtwebengine-config.pri)
+QT_FOR_CONFIG += webengine-private
+
 TARGET = QtWebEngine
 
 # For our export macros
@@ -55,7 +58,7 @@ HEADERS = \
         render_widget_host_view_qt_delegate_quickwindow.h \
         ui_delegates_manager.h
 
-isQMLTestSupportApiEnabled() {
+qtConfig(testsupport) {
     QT += testlib
 
     SOURCES += api/qquickwebenginetestsupport.cpp
diff --git a/tests/auto/quick/qmltests/qmltests.pro b/tests/auto/quick/qmltests/qmltests.pro
index ceb246dc09cfadd091dc995c74fd2c858c8f0d9a..9530e115c2406b80814f9f84943a9ecec6569136 100644
--- a/tests/auto/quick/qmltests/qmltests.pro
+++ b/tests/auto/quick/qmltests/qmltests.pro
@@ -100,7 +100,7 @@ OTHER_FILES += \
 load(qt_build_paths)
 DEFINES += QUICK_TEST_SOURCE_DIR=\\\"$$re_escape($$PWD$${QMAKE_DIR_SEP}data)\\\"
 
-!isQMLTestSupportApiEnabled() {
+!qtConfig(testsupport) {
     PLUGIN_EXTENSION = .so
     PLUGIN_PREFIX = lib
     osx: PLUGIN_PREFIX = .dylib
@@ -115,6 +115,6 @@ DEFINES += QUICK_TEST_SOURCE_DIR=\\\"$$re_escape($$PWD$${QMAKE_DIR_SEP}data)\\\"
 
     warning("QML Test Support API is disabled. This means some QML tests that use Test Support API will fail.")
     warning("Use the following command to build Test Support module and rebuild WebEngineView API:")
-    warning("cd $$BUILD_DIR && qmake WEBENGINE_CONFIG+=testsupport -r $$shell_path($$SRC_DIR/qtwebengine.pro) && make -C $$shell_path($$BUILD_DIR/src/webengine) clean && make")
+    warning("cd $$BUILD_DIR && qmake -r $$shell_path($$SRC_DIR/qtwebengine.pro -- --feature-testsupport=yes) && make -C $$shell_path($$BUILD_DIR/src/webengine) clean && make")
     warning("After performing the command above make sure QML module \"QtWebEngine.testsupport\" is deployed at $$TESTSUPPORT_MODULE")
 }
diff --git a/tests/auto/quick/quick.pro b/tests/auto/quick/quick.pro
index 8733ccac17107d6d6e76e9626b90b5adf89bb8ba..75217c1ec9168622735a7dc9f14ebfa9299346f3 100644
--- a/tests/auto/quick/quick.pro
+++ b/tests/auto/quick/quick.pro
@@ -1,3 +1,6 @@
+include($$QTWEBENGINE_OUT_ROOT/qtwebengine-config.pri)
+QT_FOR_CONFIG += webengine-private
+
 TEMPLATE = subdirs
 
 SUBDIRS += \
@@ -6,7 +9,7 @@ SUBDIRS += \
     qquickwebenginedefaultsurfaceformat \
     qquickwebengineview
 
-isQMLTestSupportApiEnabled() {
+qtConfig(testsupport) {
     SUBDIRS += \
         qmltests \
         qquickwebengineviewgraphics
diff --git a/tests/auto/quick/shared/util.h b/tests/auto/quick/shared/util.h
index 98f19bd4929b5d6f305fbc5671e41aeed07e1c9e..16456601f482216a4d3b33f77bf67ba337eaef16 100644
--- a/tests/auto/quick/shared/util.h
+++ b/tests/auto/quick/shared/util.h
@@ -115,7 +115,7 @@ inline bool waitForViewportReady(QQuickWebEngineView *webEngineView, int timeout
     Q_UNUSED(timeout)
     qFatal("Test Support API is disabled. The result is not reliable.\
             Use the following command to build Test Support module and rebuild WebEngineView API:\
-            qmake -r WEBENGINE_CONFIG+=testsupport && make");
+            qmake -r -- --feature-testsupport=yes && make");
     return false;
 #endif
 }
diff --git a/tests/auto/quick/tests.pri b/tests/auto/quick/tests.pri
index e00537b9ee7a011dad3406150a648fec12e41b29..15f6517a430c838895bc0f8e10f282afebf7997a 100644
--- a/tests/auto/quick/tests.pri
+++ b/tests/auto/quick/tests.pri
@@ -1,3 +1,6 @@
+include($$QTWEBENGINE_OUT_ROOT/qtwebengine-config.pri)
+QT_FOR_CONFIG += webengine-private
+
 TEMPLATE = app
 
 CONFIG += testcase
@@ -16,7 +19,7 @@ QT += testlib network quick webengine
 # This define is used by some tests to look up resources in the source tree
 DEFINES += TESTS_SOURCE_DIR=\\\"$$PWD/\\\"
 
-isQMLTestSupportApiEnabled() {
+qtConfig(testsupport) {
     DEFINES += ENABLE_QML_TESTSUPPORT_API
 }