fix crash when opening preference dialog

.gitignore

@@ -44,4 +44,5 @@ test.js
 /.cache/
 .clangd
 internal_docs/
-*.flatpak
+*.flatpak
+/flatpak-repo/

scripts/build_flatpak_with_docker.sh

@@ -0,0 +1,144 @@
+#!/usr/bin/env bash
+#
+# Build OrcaSlicer Flatpak locally using Docker with the same container image
+# as the CI (build_all.yml).
+#
+# Usage:
+#   ./scripts/build_flatpak_with_docker.sh [--arch <x86_64|aarch64>] [--no-debug-info]
+#
+# Requirements:
+#   - Docker (or Podman with docker compatibility)
+#
+# The resulting .flatpak bundle is placed in the project root.
+# A persistent Docker volume "flatpak-builder-cache" is used to cache
+# downloaded sources across builds. Remove it with:
+#   docker volume rm flatpak-builder-cache
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+
+# ---------- defaults ----------
+ARCH="$(uname -m)"
+NO_DEBUG_INFO=false
+NO_PULL=false
+FORCE_CLEAN=true
+CONTAINER_IMAGE="ghcr.io/flathub-infra/flatpak-github-actions:gnome-49"
+
+# ---------- parse args ----------
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --arch)
+            ARCH="$2"; shift 2 ;;
+        --no-debug-info)
+            NO_DEBUG_INFO=true; shift ;;
+        --no-pull)
+            NO_PULL=true; shift ;;
+        --keep-build)
+            FORCE_CLEAN=false; shift ;;
+        --image)
+            CONTAINER_IMAGE="$2"; shift 2 ;;
+        -h|--help)
+            echo "Usage: $0 [--arch <x86_64|aarch64>] [--no-debug-info] [--no-pull] [--keep-build] [--image <image>]"
+            exit 0 ;;
+        *)
+            echo "Unknown option: $1" >&2; exit 1 ;;
+    esac
+done
+
+# ---------- version & commit ----------
+cd "$PROJECT_ROOT"
+
+VER_PURE=$(grep 'set(SoftFever_VERSION' version.inc | cut -d '"' -f2)
+if [ -z "$VER_PURE" ]; then
+    echo "Error: could not extract version from version.inc" >&2
+    exit 1
+fi
+VER="V${VER_PURE}"
+GIT_COMMIT_HASH=$(git rev-parse HEAD)
+BUNDLE_NAME="OrcaSlicer-Linux-flatpak_${VER}_${ARCH}.flatpak"
+
+echo "=== OrcaSlicer Flatpak Build ==="
+echo "  Version:    ${VER} (${VER_PURE})"
+echo "  Commit:     ${GIT_COMMIT_HASH}"
+echo "  Arch:       ${ARCH}"
+echo "  Image:      ${CONTAINER_IMAGE}"
+echo "  Bundle:     ${BUNDLE_NAME}"
+echo "  Debug info: $([ "$NO_DEBUG_INFO" = true ] && echo "disabled" || echo "enabled")"
+echo "  ccache:     enabled"
+echo ""
+
+# ---------- prepare manifest ----------
+MANIFEST_SRC="scripts/flatpak/io.github.orcaslicer.OrcaSlicer.yml"
+MANIFEST_DOCKER="scripts/flatpak/io.github.orcaslicer.OrcaSlicer.docker.yml"
+cp "$MANIFEST_SRC" "$MANIFEST_DOCKER"
+
+# Ensure cleanup on exit (success or failure)
+trap 'rm -f "$PROJECT_ROOT/$MANIFEST_DOCKER"' EXIT
+
+# Optionally strip debug info (matches CI behaviour for faster builds)
+if [ "$NO_DEBUG_INFO" = true ]; then
+    sed -i '/^build-options:/a\  no-debuginfo: true\n  strip: true' "$MANIFEST_DOCKER"
+fi
+
+# Inject git commit hash (same sed as CI)
+sed -i "/name: OrcaSlicer/{n;s|buildsystem: simple|buildsystem: simple\n    build-options:\n      env:\n        git_commit_hash: \"$GIT_COMMIT_HASH\"|}" "$MANIFEST_DOCKER"
+
+# ---------- run build in Docker ----------
+DOCKER="${DOCKER:-docker}"
+
+if [ "$NO_PULL" = false ]; then
+    echo "=== Pulling container image ==="
+    "$DOCKER" pull "$CONTAINER_IMAGE"
+fi
+
+FORCE_CLEAN_FLAG=""
+if [ "$FORCE_CLEAN" = true ]; then
+    FORCE_CLEAN_FLAG="--force-clean"
+fi
+
+# Pass build parameters as env vars so the inner script doesn't need
+# variable expansion from the outer shell (avoids quoting issues).
+echo "=== Starting Flatpak build inside container ==="
+"$DOCKER" run --rm --privileged \
+    -v "$PROJECT_ROOT":/src:Z \
+    -v flatpak-builder-cache:/src/.flatpak-builder \
+    -w /src \
+    -e "BUILD_ARCH=$ARCH" \
+    -e "BUNDLE_NAME=$BUNDLE_NAME" \
+    -e "FORCE_CLEAN_FLAG=$FORCE_CLEAN_FLAG" \
+    "$CONTAINER_IMAGE" \
+    bash -c '
+        set -euo pipefail
+
+        # Install required SDK extensions (not pre-installed in the container image)
+        flatpak install -y --noninteractive flathub \
+            org.freedesktop.Sdk.Extension.llvm21//25.08 || true
+
+        flatpak-builder $FORCE_CLEAN_FLAG \
+            --ccache \
+            --disable-rofiles-fuse \
+            --arch="$BUILD_ARCH" \
+            --repo=flatpak-repo \
+            flatpak-build \
+            scripts/flatpak/io.github.orcaslicer.OrcaSlicer.docker.yml
+
+        flatpak build-bundle \
+            --arch="$BUILD_ARCH" \
+            flatpak-repo \
+            "$BUNDLE_NAME" \
+            io.github.orcaslicer.OrcaSlicer
+
+        # Fix ownership so output files are not root-owned on the host
+        chown "$(stat -c %u:%g /src)" "$BUNDLE_NAME" flatpak-build flatpak-repo
+
+        echo "=== Build complete ==="
+    '
+
+echo ""
+echo "=== Flatpak bundle ready ==="
+echo "  ${PROJECT_ROOT}/${BUNDLE_NAME}"
+echo ""
+echo "Install with:"
+echo "  flatpak install --user ${BUNDLE_NAME}"

scripts/flatpak/.gitignore

@@ -1,2 +1,3 @@
 builddir
 .flatpak-builder
+*.docker.yml

scripts/flatpak/io.github.orcaslicer.OrcaSlicer.yml

@@ -333,6 +333,11 @@ modules:
 
       - install -Dm644 LICENSE.txt /app/share/licenses/${FLATPAK_ID}/LICENSE.txt
 
+      - | # Install fonts into fontconfig-scanned directory so Pango finds them
+        # before initialization (avoids ensure_faces crash from AddPrivateFont)
+        install -Dm644 -t /app/share/fonts/OrcaSlicer/ resources/fonts/*.ttf
+        fc-cache -f /app/share/fonts/OrcaSlicer/
+
     sources:
       # OrcaSlicer source tree (specific dirs to avoid copying .git from worktree)
       - type: dir

src/slic3r/GUI/GUI_App.cpp

@@ -6199,7 +6199,7 @@ static const wxLanguageInfo* linux_get_existing_locale_language(const wxLanguage
         if (! it->empty()) {
             const std::string &locale = *it;
             const wxLanguageInfo* lang = wxLocale::FindLanguageInfo(from_u8(locale));
-            if (wxLocale::IsAvailable(lang->Language))
+            if (lang != nullptr && wxLocale::IsAvailable(lang->Language))
                 return lang;
         }
     return language;
@@ -6241,7 +6241,10 @@ bool GUI_App::select_language()
     names.Alloc(language_infos.size());
 
     // Some valid language should be selected since the application start up.
-    const wxLanguage current_language = wxLanguage(m_wxLocale->GetLanguage());
+    const wxString active_language_code = current_language_code();
+    const wxLanguageInfo* active_language_info = wxLocale::FindLanguageInfo(active_language_code);
+    const wxLanguage current_language = active_language_info != nullptr ? wxLanguage(active_language_info->Language) : wxLanguage(m_wxLocale->GetLanguage());
+    const wxString active_lang_prefix = active_language_code.BeforeFirst('_');
     int 		     init_selection   		= -1;
     int 			 init_selection_alt     = -1;
     int 			 init_selection_default = -1;
@@ -6249,9 +6252,9 @@ bool GUI_App::select_language()
         if (wxLanguage(language_infos[i]->Language) == current_language)
         	// The dictionary matches the active language and country.
             init_selection = i;
-        else if ((language_infos[i]->CanonicalName.BeforeFirst('_') == m_wxLocale->GetCanonicalName().BeforeFirst('_')) ||
+        else if ((language_infos[i]->CanonicalName.BeforeFirst('_') == active_lang_prefix) ||
         		 // if the active language is Slovak, mark the Czech language as active.
-        	     (language_infos[i]->CanonicalName.BeforeFirst('_') == "cs" && m_wxLocale->GetCanonicalName().BeforeFirst('_') == "sk"))
+        	     (language_infos[i]->CanonicalName.BeforeFirst('_') == "cs" && active_lang_prefix == "sk"))
         	// The dictionary matches the active language, it does not necessarily match the country.
         	init_selection_alt = i;
         if (language_infos[i]->CanonicalName.BeforeFirst('_') == "en")
@@ -6369,7 +6372,10 @@ bool GUI_App::load_language(wxString language, bool initial)
 			language_info = wxLocale::GetLanguageInfo(wxLANGUAGE_ENGLISH_US);
     }
 
-	BOOST_LOG_TRIVIAL(trace) << boost::format("Switching wxLocales to %1%") % language_info->CanonicalName.ToUTF8().data();
+    const wxLanguageInfo *translation_language_info = language_info;
+    const wxString requested_language_code = translation_language_info->CanonicalName;
+    const wxLanguageInfo *locale_language_info = translation_language_info;
+    BOOST_LOG_TRIVIAL(trace) << boost::format("Requested translation language %1%") % requested_language_code.ToUTF8().data();
 
     // Select language for locales. This language may be different from the language of the dictionary.
     //if (language_info == m_language_info_best || language_info == m_language_info_system) {
@@ -6382,8 +6388,8 @@ bool GUI_App::load_language(wxString language, bool initial)
     //    language_info = m_language_info_system;
 
     // Alternate language code.
-    wxLanguage language_dict = wxLanguage(language_info->Language);
+    wxLanguage language_dict = wxLanguage(translation_language_info->Language);
-    if (language_info->CanonicalName.BeforeFirst('_') == "sk") {
+    if (translation_language_info->CanonicalName.BeforeFirst('_') == "sk") {
     	// Slovaks understand Czech well. Give them the Czech translation.
     	language_dict = wxLANGUAGE_CZECH;
 		BOOST_LOG_TRIVIAL(info) << "Using Czech dictionaries for Slovak language";
@@ -6392,19 +6398,34 @@ bool GUI_App::load_language(wxString language, bool initial)
 #ifdef __linux__
     // If we can't find this locale , try to use different one for the language
     // instead of just reporting that it is impossible to switch.
-    if (! wxLocale::IsAvailable(language_info->Language) && m_language_info_system) {
+    if (!wxLocale::IsAvailable(locale_language_info->Language) && m_language_info_system) {
-        std::string original_lang = into_u8(language_info->CanonicalName);
+        std::string original_lang = into_u8(locale_language_info->CanonicalName);
-        language_info = linux_get_existing_locale_language(language_info, m_language_info_system);
+        locale_language_info = linux_get_existing_locale_language(locale_language_info, m_language_info_system);
-        BOOST_LOG_TRIVIAL(info) << boost::format("Can't switch language to %1% (missing locales). Using %2% instead.")
+        if (locale_language_info != nullptr && locale_language_info != translation_language_info) {
-                                    % original_lang % language_info->CanonicalName.ToUTF8().data();
+            BOOST_LOG_TRIVIAL(info) << boost::format("Can't use locale %1% directly (missing locales). Using locale %2% instead.")
+                                        % original_lang % locale_language_info->CanonicalName.ToUTF8().data();
+        }
+    }
+
+    if (locale_language_info == nullptr || !wxLocale::IsAvailable(locale_language_info->Language)) {
+        auto try_locale = [](const wxLanguageInfo* candidate) -> const wxLanguageInfo* {
+            return (candidate && wxLocale::IsAvailable(candidate->Language)) ? candidate : nullptr;
+        };
+        const wxLanguageInfo* fallback_locale_info =
+            try_locale(m_wxLocale ? wxLocale::GetLanguageInfo(wxLanguage(m_wxLocale->GetLanguage())) : nullptr);
+        if (!fallback_locale_info) fallback_locale_info = try_locale(m_language_info_system);
+        if (!fallback_locale_info) fallback_locale_info = try_locale(m_language_info_best);
+        if (!fallback_locale_info) fallback_locale_info = try_locale(wxLocale::GetLanguageInfo(wxLANGUAGE_ENGLISH_US));
+        if (!fallback_locale_info) fallback_locale_info = try_locale(wxLocale::GetLanguageInfo(wxLANGUAGE_ENGLISH_UK));
+        if (fallback_locale_info != nullptr) {
+            BOOST_LOG_TRIVIAL(info) << boost::format("Using fallback locale %1% while keeping translation dictionary %2%.")
+                                        % fallback_locale_info->CanonicalName.ToUTF8().data() % requested_language_code.ToUTF8().data();
+            locale_language_info = fallback_locale_info;
+        }
     }
 #endif
 
-    if (! wxLocale::IsAvailable(language_info->Language)&&initial) {
+    if (initial) {
-        language_info = wxLocale::GetLanguageInfo(wxLANGUAGE_ENGLISH_UK);
-        app_config->set("language", language_info->CanonicalName.ToUTF8().data());
-    }
-    else if (initial) {
         // bbs supported languages
         //TODO: use a global one with Preference
         //wxLanguage supported_languages[]{
@@ -6438,9 +6459,11 @@ bool GUI_App::load_language(wxString language, bool initial)
         //}
     }
 
-    if (! wxLocale::IsAvailable(language_info->Language)) {
+	BOOST_LOG_TRIVIAL(trace) << boost::format("Switching wxLocales to %1%") % locale_language_info->CanonicalName.ToUTF8().data();
+
+    if (!wxLocale::IsAvailable(locale_language_info->Language)) {
     	// Loading the language dictionary failed.
-    	wxString message = "Switching Orca Slicer to language " + language_info->CanonicalName + " failed.";
+	    wxString message = "Switching Orca Slicer to language " + requested_language_code + " failed.";
 #if !defined(_WIN32) && !defined(__APPLE__)
         // likely some linux system
         message += "\nYou may need to reconfigure the missing locales, likely by running the \"locale-gen\" and \"dpkg-reconfigure locales\" commands.\n";
@@ -6458,12 +6481,13 @@ bool GUI_App::load_language(wxString language, bool initial)
     //FIXME wxWidgets cause havoc if the current locale is deleted. We just forget it causing memory leaks for now.
     m_wxLocale.release();
     m_wxLocale = Slic3r::make_unique<wxLocale>();
-    m_wxLocale->Init(language_info->Language);
+    m_wxLocale->Init(locale_language_info->Language);
     // Override language at the active wxTranslations class (which is stored in the active m_wxLocale)
     // to load possibly different dictionary, for example, load Czech dictionary for Slovak language.
     wxTranslations::Get()->SetLanguage(language_dict);
     m_wxLocale->AddCatalog(SLIC3R_APP_KEY);
-    m_imgui->set_language(into_u8(language_info->CanonicalName));
+    m_active_language_code = requested_language_code;
+    m_imgui->set_language(into_u8(requested_language_code));
 
     //FIXME This is a temporary workaround, the correct solution is to switch to "C" locale during file import / export only.
     //wxSetlocale(LC_NUMERIC, "C");
@@ -6751,49 +6775,57 @@ void  GUI_App::show_ip_address_enter_dialog_handler(wxCommandEvent& evt)
 
 void GUI_App::open_preferences(size_t open_on_tab, const std::string& highlight_option)
 {
-    bool app_layout_changed = false;
+    bool need_recreate_gui = false;
+    std::string pending_language;
     {
         // the dialog needs to be destroyed before the call to recreate_GUI()
         // or sometimes the application crashes into wxDialogBase() destructor
         // so we put it into an inner scope
         PreferencesDialog dlg(mainframe, open_on_tab, highlight_option);
         dlg.ShowModal();
-        this->plater_->get_current_canvas3D()->force_set_focus();
+        need_recreate_gui = dlg.recreate_GUI();
-        // BBS
+        pending_language = dlg.pending_language();
-        //app_layout_changed = dlg.settings_layout_changed();
+        if (!need_recreate_gui) {
+            this->plater_->get_current_canvas3D()->force_set_focus();
 #if ENABLE_GCODE_LINES_ID_IN_H_SLIDER
-        if (dlg.seq_top_layer_only_changed() || dlg.seq_seq_top_gcode_indices_changed())
+            if (dlg.seq_top_layer_only_changed() || dlg.seq_seq_top_gcode_indices_changed())
 #else
-        if (dlg.seq_top_layer_only_changed())
+            if (dlg.seq_top_layer_only_changed())
 #endif // ENABLE_GCODE_LINES_ID_IN_H_SLIDER
-            this->plater_->reload_print();
+                this->plater_->reload_print();
 #ifdef _WIN32
-        if (is_editor()) {
+            if (is_editor()) {
-            if (app_config->get("associate_3mf") == "true")
+                if (app_config->get("associate_3mf") == "true")
-                associate_files(L"3mf");
+                    associate_files(L"3mf");
-            if (app_config->get("associate_stl") == "true")
+                if (app_config->get("associate_stl") == "true")
-                associate_files(L"stl");
+                    associate_files(L"stl");
-            if (app_config->get("associate_step") == "true") {
+                if (app_config->get("associate_step") == "true") {
-                associate_files(L"step");
+                    associate_files(L"step");
-                associate_files(L"stp");
+                    associate_files(L"stp");
+                }
+                associate_url(L"orcaslicer");
+            }
+            else {
+                if (app_config->get("associate_gcode") == "true")
+                    associate_files(L"gcode");
             }
-            associate_url(L"orcaslicer");
-        }
-        else {
-            if (app_config->get("associate_gcode") == "true")
-                associate_files(L"gcode");
-        }
 #endif // _WIN32
+        }
     }
 
-    // BBS
+    if (!pending_language.empty()) {
-    /*
+        const std::string previous_language = app_config->get("language");
-    if (app_layout_changed) {
+        app_config->set("language", pending_language);
-        // hide full main_sizer for mainFrame
+        if (!load_language(wxString::FromUTF8(pending_language), false)) {
-        mainframe->GetSizer()->Show(false);
+            app_config->set("language", previous_language);
-        mainframe->update_layout();
+            if (this->plater_)
-        mainframe->select_tab(size_t(0));
+                this->plater_->get_current_canvas3D()->force_set_focus();
-    }*/
+            return;
+        }
+    }
+
+    if (need_recreate_gui)
+        recreate_GUI(_L("Changing application language"));
 }
 
 bool GUI_App::has_unsaved_preset_changes() const

src/slic3r/GUI/GUI_App.hpp

@@ -273,6 +273,7 @@ private:
     const wxLanguageInfo		 *m_language_info_system = nullptr;
     // Best translation language, provided by Windows or OSX, owned by wxWidgets.
     const wxLanguageInfo		 *m_language_info_best   = nullptr;
+    wxString                    m_active_language_code;
 
     OpenGLManager m_opengl_mgr;
     std::unique_ptr<RemovableDriveManager> m_removable_drive_manager;
@@ -563,7 +564,7 @@ public:
     void            preset_deleted_from_cloud(std::string setting_id);
 
     wxString        filter_string(wxString str);
-    wxString        current_language_code() const { return m_wxLocale->GetCanonicalName(); }
+	wxString        current_language_code() const { return m_active_language_code.empty() && m_wxLocale ? m_wxLocale->GetCanonicalName() : m_active_language_code; }
 	// Translate the language code to a code, for which Prusa Research maintains translations. Defaults to "en_US".
     wxString 		current_language_code_safe() const;
     bool            is_localized() const { return m_wxLocale->GetLocale() != "English"; }

src/slic3r/GUI/MainFrame.cpp

@@ -3145,15 +3145,7 @@ void MainFrame::init_menubar_as_editor()
     append_menu_item(
         parent_menu, wxID_ANY, _L("Preferences") + "\t" + ctrl + ",", "",
         [this](wxCommandEvent &) {
-            PreferencesDialog dlg(this);
+            wxGetApp().open_preferences();
-            dlg.ShowModal();
-            plater()->get_current_canvas3D()->force_set_focus();
-#if ENABLE_GCODE_LINES_ID_IN_H_SLIDER
-            if (dlg.seq_top_layer_only_changed() || dlg.seq_seq_top_gcode_indices_changed())
-#else
-            if (dlg.seq_top_layer_only_changed())
-#endif
-                plater()->reload_print();
         },
         "", nullptr, []() { return true; }, this, 1);
     //parent_menu->Insert(1, preference_item);
@@ -3174,7 +3166,6 @@ void MainFrame::init_menubar_as_editor()
         [this](wxCommandEvent &) {
             // Orca: Use GUI_App::open_preferences instead of direct call so windows associations are updated on exit
             wxGetApp().open_preferences();
-            plater()->get_current_canvas3D()->force_set_focus();
         },
         "", nullptr, []() { return true; }, this);
     //m_topbar->AddDropDownMenuItem(preference_item);

src/slic3r/GUI/Preferences.cpp

@@ -318,13 +318,10 @@ wxBoxSizer *PreferencesDialog::create_item_language_combobox(wxString title, wxS
 
             m_current_language_selected = combobox->GetSelection();
             if (m_current_language_selected >= 0 && m_current_language_selected < vlist.size()) {
-                app_config->set(param, vlist[m_current_language_selected]->CanonicalName.ToUTF8().data());
+                m_pending_language = vlist[m_current_language_selected]->CanonicalName.ToUTF8().data();
-
+                m_recreate_GUI = true;
-                wxGetApp().load_language(vlist[m_current_language_selected]->CanonicalName, false);
+                EndModal(wxID_OK);
-                Close();
+                return;
-                // Reparent(nullptr);
-                GetParent()->RemoveChild(this);
-                wxGetApp().recreate_GUI(_L("Changing application language"));
             }
         }
 

src/slic3r/GUI/Preferences.hpp

@@ -6,6 +6,7 @@
 
 #include <wx/dialog.h>
 #include <wx/timer.h>
+#include <string>
 #include <vector>
 #include <list>
 #include <map>
@@ -43,10 +44,12 @@ protected:
     // bool								m_settings_layout_changed {false};
     bool m_seq_top_layer_only_changed{false};
     bool m_recreate_GUI{false};
+    std::string m_pending_language;
 
 public:
     bool seq_top_layer_only_changed() const { return m_seq_top_layer_only_changed; }
     bool recreate_GUI() const { return m_recreate_GUI; }
+    const std::string& pending_language() const { return m_pending_language; }
     void on_dpi_changed(const wxRect &suggested_rect) override;
 
 public:

src/slic3r/GUI/Widgets/Label.cpp

@@ -5,6 +5,9 @@
 #include <wx/dcclient.h>
 #include <wx/settings.h>
 #include <boost/log/trivial.hpp>
+#ifdef __linux__
+#include <fontconfig/fontconfig.h>
+#endif
 
 
 wxFont Label::sysFont(int size, bool bold)
@@ -58,27 +61,46 @@ wxFont Label::Body_10;
 wxFont Label::Body_9;
 wxFont Label::Body_8;
 
+// Check if a font family is already available via fontconfig.
+#ifdef __linux__
+static bool fc_font_available(const char *family_name)
+{
+    FcPattern *pat = FcPatternCreate();
+    if (!pat)
+        return false;
+    FcPatternAddString(pat, FC_FAMILY, (const FcChar8 *) family_name);
+    FcResult res;
+    FcPattern *match = FcFontMatch(nullptr, pat, &res);
+    bool available = false;
+    if (match) {
+        FcChar8 *matched_family = nullptr;
+        if (FcPatternGetString(match, FC_FAMILY, 0, &matched_family) == FcResultMatch && matched_family)
+            available = (strcasecmp((const char *) matched_family, family_name) == 0);
+        FcPatternDestroy(match);
+    }
+    FcPatternDestroy(pat);
+    return available;
+}
+#endif
+
 void Label::initSysFont()
 {
 #if defined(__linux__) || defined(_WIN32)
-    const std::string &resource_path = Slic3r::resources_dir();
+    // On Linux, skip AddPrivateFont for fonts already known to fontconfig
-    wxString font_path = wxString::FromUTF8(resource_path + "/fonts/HarmonyOS_Sans_SC_Bold.ttf");
+    // (e.g. installed system-wide in a Flatpak).  Calling AddPrivateFont
-    bool result = wxFont::AddPrivateFont(font_path);
+    // triggers a Pango crash in ensure_faces() on Pango >= 1.48 (GNOME 49+),
-    // BOOST_LOG_TRIVIAL(info) << boost::format("add font of HarmonyOS_Sans_SC_Bold returns %1%")%result;
+    // because FcConfigAppFontAddFile invalidates Pango's cached font map.
-    // printf("add font of HarmonyOS_Sans_SC_Bold returns %d\n", result);
+    bool load_fonts = true;
-    font_path = wxString::FromUTF8(resource_path + "/fonts/HarmonyOS_Sans_SC_Regular.ttf");
+#ifdef __linux__
-    result = wxFont::AddPrivateFont(font_path);
+    load_fonts = !fc_font_available("HarmonyOS Sans SC") || !fc_font_available("NanumGothic");
-    // BOOST_LOG_TRIVIAL(info) << boost::format("add font of HarmonyOS_Sans_SC_Regular returns %1%")%result;
+#endif
-    // printf("add font of HarmonyOS_Sans_SC_Regular returns %d\n", result);
+    if (load_fonts) {
-    // Adding NanumGothic Regular and Bold
+        const std::string &resource_path = Slic3r::resources_dir();
-    font_path = wxString::FromUTF8(resource_path + "/fonts/NanumGothic-Regular.ttf");
+        wxFont::AddPrivateFont(wxString::FromUTF8(resource_path + "/fonts/HarmonyOS_Sans_SC_Bold.ttf"));
-    result = wxFont::AddPrivateFont(font_path);
+        wxFont::AddPrivateFont(wxString::FromUTF8(resource_path + "/fonts/HarmonyOS_Sans_SC_Regular.ttf"));
-    // BOOST_LOG_TRIVIAL(info) << boost::format("add font of NanumGothic-Regular returns %1%")%result;
+        wxFont::AddPrivateFont(wxString::FromUTF8(resource_path + "/fonts/NanumGothic-Regular.ttf"));
-    // printf("add font of NanumGothic-Regular returns %d\n", result);
+        wxFont::AddPrivateFont(wxString::FromUTF8(resource_path + "/fonts/NanumGothic-Bold.ttf"));
-    font_path = wxString::FromUTF8(resource_path + "/fonts/NanumGothic-Bold.ttf");
+    }
-    result = wxFont::AddPrivateFont(font_path);
-    // BOOST_LOG_TRIVIAL(info) << boost::format("add font of NanumGothic-Bold returns %1%")%result;
-    // printf("add font of NanumGothic-Bold returns %d\n", result);
 #endif
     Head_48 = Label::sysFont(48, true);
     Head_32 = Label::sysFont(32, true);