diff --git a/toonz/sources/toonz/insertfxpopup.cpp b/toonz/sources/toonz/insertfxpopup.cpp
index a2e497b..655c104 100644
--- a/toonz/sources/toonz/insertfxpopup.cpp
+++ b/toonz/sources/toonz/insertfxpopup.cpp
@@ -276,20 +276,20 @@ InsertFxPopup::InsertFxPopup()
   addWidget(m_fxTree);
 
   QPushButton *insertBtn = new QPushButton(tr("Insert"), this);
-  insertBtn->setFixedSize(65, 25);
+  insertBtn->setMinimumSize(65, 25);
   insertBtn->setObjectName("PushButton_NoPadding");
   connect(insertBtn, SIGNAL(clicked()), this, SLOT(onInsert()));
   insertBtn->setDefault(true);
   m_buttonLayout->addWidget(insertBtn);
 
   QPushButton *addBtn = new QPushButton(tr("Add"), this);
-  addBtn->setFixedSize(65, 25);
+  addBtn->setMinimumSize(65, 25);
   addBtn->setObjectName("PushButton_NoPadding");
   connect(addBtn, SIGNAL(clicked()), this, SLOT(onAdd()));
   m_buttonLayout->addWidget(addBtn);
 
   QPushButton *replaceBtn = new QPushButton(tr("Replace"), this);
-  replaceBtn->setFixedHeight(25);
+  replaceBtn->setMinimumSize(65, 25);
   replaceBtn->setObjectName("PushButton_NoPadding");
   connect(replaceBtn, SIGNAL(clicked()), this, SLOT(onReplace()));
   m_buttonLayout->addWidget(replaceBtn);