diff --git a/toonz/sources/common/tfx/trenderer.cpp b/toonz/sources/common/tfx/trenderer.cpp
index 638e310..60ea393 100644
--- a/toonz/sources/common/tfx/trenderer.cpp
+++ b/toonz/sources/common/tfx/trenderer.cpp
@@ -1424,8 +1424,6 @@ void TRendererImp::startRendering(
         QThread::currentThread() == qGuiApp->thread()) {
       rs.m_offScreenSurface.reset(new QOffscreenSurface());
       rs.m_offScreenSurface->setFormat(QSurfaceFormat::defaultFormat());
-      rs.m_offScreenSurface->setScreen(
-          QOpenGLContext::globalShareContext()->screen());
       rs.m_offScreenSurface->create();
     }
 
diff --git a/toonz/sources/tcomposer/tcomposer.cpp b/toonz/sources/tcomposer/tcomposer.cpp
index 5c0bf88..e38633c 100644
--- a/toonz/sources/tcomposer/tcomposer.cpp
+++ b/toonz/sources/tcomposer/tcomposer.cpp
@@ -564,7 +564,6 @@ static std::pair<int, int> generateMovie(ToonzScene *scene, const TFilePath &fp,
 DV_IMPORT_API void initStdFx();
 DV_IMPORT_API void initColorFx();
 int main(int argc, char *argv[]) {
-  QCoreApplication::setAttribute(Qt::AA_ShareOpenGLContexts);
   QApplication app(argc, argv);
 
   // Create a QObject destroyed just before app - see Tnz6's main.cpp for
diff --git a/toonz/sources/toonz/main.cpp b/toonz/sources/toonz/main.cpp
index 3619742..34f6edd 100644
--- a/toonz/sources/toonz/main.cpp
+++ b/toonz/sources/toonz/main.cpp
@@ -259,9 +259,6 @@ int main(int argc, char *argv[]) {
 #if QT_VERSION >= 0x050600
   QApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 #endif
-  // Enables resource sharing between the OpenGL contexts used by classes like
-  // QOpenGLWidget and QQuickWidget.
-  QCoreApplication::setAttribute(Qt::AA_ShareOpenGLContexts);
 
   QApplication a(argc, argv);
 
diff --git a/toonz/sources/toonzlib/imagebuilders.cpp b/toonz/sources/toonzlib/imagebuilders.cpp
index 5d48b7d..3e25b73 100644
--- a/toonz/sources/toonzlib/imagebuilders.cpp
+++ b/toonz/sources/toonzlib/imagebuilders.cpp
@@ -277,8 +277,6 @@ TImageP ImageRasterizer::build(int imFlags, void *extData) {
 
         std::unique_ptr<QOffscreenSurface> surface(new QOffscreenSurface());
         surface->setFormat(format);
-        // Enabling Qt::AA_ShareOpenGLContexts attribute in main()
-        surface->setScreen(QOpenGLContext::globalShareContext()->screen());
         surface->create();
 
         TRaster32P ras(d);
diff --git a/toonz/sources/toonzlib/plasticdeformerfx.cpp b/toonz/sources/toonzlib/plasticdeformerfx.cpp
index 9f3ea0c..2a2b981 100644
--- a/toonz/sources/toonzlib/plasticdeformerfx.cpp
+++ b/toonz/sources/toonzlib/plasticdeformerfx.cpp
@@ -363,7 +363,8 @@ void PlasticDeformerFx::doCompute(TTile &tile, double frame,
 
     // Prepare an OpenGL context
     context = new QOpenGLContext();
-    context->setShareContext(QOpenGLContext::globalShareContext());
+    if (QOpenGLContext::currentContext())
+      context->setShareContext(QOpenGLContext::currentContext());
     context->setFormat(QSurfaceFormat::defaultFormat());
     context->create();
     context->makeCurrent(info.m_offScreenSurface.get());
diff --git a/toonz/sources/toonzlib/toonzscene.cpp b/toonz/sources/toonzlib/toonzscene.cpp
index 60a3ccc..e36d56c 100644
--- a/toonz/sources/toonzlib/toonzscene.cpp
+++ b/toonz/sources/toonzlib/toonzscene.cpp
@@ -811,8 +811,6 @@ void ToonzScene::renderFrame(const TRaster32P &ras, int row, const TXsheet *xsh,
 
   std::unique_ptr<QOffscreenSurface> surface(new QOffscreenSurface());
   surface->setFormat(format);
-  // Enabling Qt::AA_ShareOpenGLContexts attribute in main()
-  surface->setScreen(QOpenGLContext::globalShareContext()->screen());
   surface->create();
 
   glPushAttrib(GL_ALL_ATTRIB_BITS);