diff --git a/src/slic3r/GUI/GUI_Utils.hpp b/src/slic3r/GUI/GUI_Utils.hpp
index 8cefb68d0..d7bf2a014 100644
--- a/src/slic3r/GUI/GUI_Utils.hpp
+++ b/src/slic3r/GUI/GUI_Utils.hpp
@@ -65,8 +65,8 @@ public:
 		if (std::abs(m_scale_factor - scale_primary_display) > 1e-6)
 			m_normal_font = m_normal_font.Scale(m_scale_factor / scale_primary_display);
 
-        // An analog of em_unit value from GUI_App.
-        m_em_unit = std::max<size_t>(10, 10 * m_scale_factor);
+        // initialize default width_unit according to the width of the one symbol ("m") of the currently active font of this window.
+        m_em_unit = std::max<size_t>(10, this->GetTextExtent("m").x - 1/*10 * m_scale_factor*/);
 
 //        recalc_font();
 
diff --git a/src/slic3r/GUI/MainFrame.cpp b/src/slic3r/GUI/MainFrame.cpp
index 296776da4..f1526aaf6 100644
--- a/src/slic3r/GUI/MainFrame.cpp
+++ b/src/slic3r/GUI/MainFrame.cpp
@@ -42,7 +42,7 @@ DPIFrame(NULL, wxID_ANY, "", wxDefaultPosition, wxDefaultSize, wxDEFAULT_FRAME_S
     this->SetFont(this->normal_font());
 #endif
     // initialize default width_unit according to the width of the one symbol ("m") of the currently active font of this window.
-    wxGetApp().set_em_unit(std::max<size_t>(10, GetTextExtent("m").x - 1));
+//     wxGetApp().set_em_unit(std::max<size_t>(10, GetTextExtent("m").x - 1));
 
     // Load the icon either from the exe, or from the ico file.
 #if _WIN32
@@ -316,7 +316,7 @@ void MainFrame::on_dpi_changed(const wxRect &suggested_rect)
     wxGetApp().update_fonts();
     this->SetFont(this->normal_font());
     // initialize default width_unit according to the width of the one symbol ("m") of the currently active font of this window.
-    wxGetApp().set_em_unit(std::max<size_t>(10, GetTextExtent("m").x - 1));
+//     wxGetApp().set_em_unit(std::max<size_t>(10, GetTextExtent("m").x - 1));
 
     /* Load default preset bitmaps before a tabpanel initialization,
      * but after filling of an em_unit value
diff --git a/src/slic3r/GUI/Tab.cpp b/src/slic3r/GUI/Tab.cpp
index a9f63afd8..acd1b9087 100644
--- a/src/slic3r/GUI/Tab.cpp
+++ b/src/slic3r/GUI/Tab.cpp
@@ -178,7 +178,7 @@ void Tab::create_preset_tab()
     // Sizer with buttons for mode changing
     m_mode_sizer = new ModeSizer(panel);
 
-    const float scale_factor = wxGetApp().em_unit()*0.1;// GetContentScaleFactor();
+    const float scale_factor = /*wxGetApp().*/em_unit(this)*0.1;// GetContentScaleFactor();
 	m_hsizer = new wxBoxSizer(wxHORIZONTAL);
 	sizer->Add(m_hsizer, 0, wxEXPAND | wxBOTTOM, 3);
 	m_hsizer->Add(m_presets_choice, 0, wxLEFT | wxRIGHT | wxTOP | wxALIGN_CENTER_VERTICAL, 3);
@@ -212,7 +212,8 @@ void Tab::create_preset_tab()
     m_treectrl = new wxTreeCtrl(panel, wxID_ANY, wxDefaultPosition, wxSize(20 * m_em_unit, -1),
 		wxTR_NO_BUTTONS | wxTR_HIDE_ROOT | wxTR_SINGLE | wxTR_NO_LINES | wxBORDER_SUNKEN | wxWANTS_CHARS);
 	m_left_sizer->Add(m_treectrl, 1, wxEXPAND);
-    m_icons = new wxImageList(int(16 * scale_factor), int(16 * scale_factor), true, 1);
+    const int img_sz = int(16 * scale_factor + 0.5f);
+    m_icons = new wxImageList(img_sz, img_sz, true, 1);
 	// Index of the last icon inserted into $self->{icons}.
 	m_icon_count = -1;
 	m_treectrl->AssignImageList(m_icons);