diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index 8d72405cdd..6921a72271 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -9780,18 +9780,18 @@ void GLCanvas3D::_render_paint_toolbar() const
         ImVec2 number_label_size = ImGui::CalcTextSize(std::to_string(i + 1).c_str());
         ImGui::SetCursorPosY(cursor_y + text_offset_y);
         ImGui::SetCursorPosX(spacing + i * (spacing + button_size.x) + (button_size.x - number_label_size.x) / 2);
-        ImGui::TextColored(text_color, std::to_string(i + 1).c_str());
+        ImGui::TextColored(text_color, "%s", std::to_string(i + 1).c_str());
         imgui.pop_bold_font();
 
         ImVec2 filament_first_line_label_size = ImGui::CalcTextSize(filament_text_first_line[i].c_str());
         ImGui::SetCursorPosY(cursor_y + text_offset_y + number_label_size.y);
         ImGui::SetCursorPosX(spacing + i * (spacing + button_size.x) + (button_size.x - filament_first_line_label_size.x) / 2);
-        ImGui::TextColored(text_color, filament_text_first_line[i].c_str());
+        ImGui::TextColored(text_color, "%s", filament_text_first_line[i].c_str());
 
         ImVec2 filament_second_line_label_size = ImGui::CalcTextSize(filament_text_second_line[i].c_str());
         ImGui::SetCursorPosY(cursor_y + text_offset_y + number_label_size.y + filament_first_line_label_size.y);
         ImGui::SetCursorPosX(spacing + i * (spacing + button_size.x) + (button_size.x - filament_second_line_label_size.x) / 2);
-        ImGui::TextColored(text_color, filament_text_second_line[i].c_str());
+        ImGui::TextColored(text_color, "%s", filament_text_second_line[i].c_str());
     }
 
     if (ImGui::GetWindowWidth() == constraint_window_width) {
@@ -10018,9 +10018,9 @@ void GLCanvas3D::_render_assemble_info() const
     double size1 = m_selection.get_bounding_box().size()(1);
     double size2 = m_selection.get_bounding_box().size()(2);
     if (!m_selection.is_empty()) {
-        ImGui::Text(_L("Volume:").ToUTF8()); ImGui::SameLine(caption_max);
+        ImGui::Text("%s", _L("Volume:").ToUTF8().data()); ImGui::SameLine(caption_max);
         ImGui::Text("%.2f", size0 * size1 * size2);
-        ImGui::Text(_L("Size:").ToUTF8()); ImGui::SameLine(caption_max);
+        ImGui::Text("%s", _L("Size:").ToUTF8().data()); ImGui::SameLine(caption_max);
         ImGui::Text("%.2f x %.2f x %.2f", size0, size1, size2);
     }
     imgui->end();
diff --git a/src/slic3r/GUI/Gizmos/GLGizmoSimplify.cpp b/src/slic3r/GUI/Gizmos/GLGizmoSimplify.cpp
index f4fa1fbbb9..6a08d5eff4 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmoSimplify.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmoSimplify.cpp
@@ -343,12 +343,12 @@ void GLGizmoSimplify::on_render_input_window(float x, float y, float bottom_limi
     ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing,ImVec2(10,20));
     if (is_worker_running) { // apply or preview
         // draw progress bar
-        std::string progress_text = GUI::format("%1%", std::to_string(progress)) + "%%";
+        std::string progress_text = GUI::format("%1%", std::to_string(progress)) + "%";
         ImVec2 progress_size(bottom_left_width - space_size, 0.0f);
         ImGui::BBLProgressBar2(progress / 100., progress_size);
         ImGui::SameLine();
         ImGui::AlignTextToFramePadding();
-        ImGui::TextColored(ImVec4(0.42f, 0.42f, 0.42f, 1.00f), progress_text.c_str());
+        ImGui::TextColored(ImVec4(0.42f, 0.42f, 0.42f, 1.00f), "%s", progress_text.c_str());
         ImGui::SameLine(bottom_left_width + slider_width +  m_imgui->scaled(1.0f));
     } else {
         ImGui::Dummy(ImVec2(bottom_left_width - space_size, -1));