diff --git a/sources/qetdiagrameditor.cpp b/sources/qetdiagrameditor.cpp
index 57ef6ec2f..5b2ba6779 100644
--- a/sources/qetdiagrameditor.cpp
+++ b/sources/qetdiagrameditor.cpp
@@ -45,6 +45,7 @@
 #include "ui/backupdialog.h"
 #include "ui/dialogwaiting.h"
 #include "undocommand/addelementtextcommand.h"
+#include "utils/qetutils.h"
 #include "undocommand/rotateselectioncommand.h"
 #include "undocommand/rotatetextscommand.h"
 #include "diagram.h"
@@ -1184,6 +1185,13 @@ bool QETDiagramEditor::openAndAddProject(
 	//Create the project
 	DialogWaiting::instance(this);
 
+		//Per-project window for the font counters reported below; the folios
+		//(and with them the stored font descriptions) are built between here
+		//and the end of addProject(). RAII, because DialogWaiting pumps the
+		//event loop during the load: a nested openAndAddProject() gets its
+		//own window and this one resumes unharmed.
+	QETUtils::FontRestorationScope font_scope;
+
 	QETProject *project = new QETProject(filepath);
 	if (project -> state() != QETProject::Ok)
 	{
@@ -1210,6 +1218,42 @@ bool QETDiagramEditor::openAndAddProject(
 	addProject(project);
 	DialogWaiting::dropInstance();
 
+		//Report font descriptions which could not be read as-is (written by
+		//an incompatible Qt version or corrupted), so the user learns about
+		//it from somewhere else than the console. See issue #553.
+	const int salvaged_fonts = font_scope.salvaged();
+	const int unreadable_fonts = font_scope.unreadable();
+	if (salvaged_fonts || unreadable_fonts)
+	{
+		qInfo().nospace() << "Project font descriptions: "
+				  << salvaged_fonts << " salvaged from a foreign format, "
+				  << unreadable_fonts << " unreadable (default font applies)";
+	}
+	if (interactive && (salvaged_fonts || unreadable_fonts))
+	{
+		QStringList details;
+		if (salvaged_fonts) {
+			details << tr("%n description(s) de police écrite(s) dans un "
+					  "format étranger ou corrompu ont été restaurée(s). "
+					  "Elles seront réécrites dans un format stable au "
+					  "prochain enregistrement du projet.",
+					  "message box content",
+					  salvaged_fonts);
+		}
+		if (unreadable_fonts) {
+			details << tr("%n description(s) de police n'ont pas pu être "
+					  "lue(s) ; la police par défaut sera utilisée pour "
+					  "ces textes.",
+					  "message box content",
+					  unreadable_fonts);
+		}
+		QET::QetMessageBox::information(
+			this,
+			tr("Polices du projet", "message box title"),
+			details.join("\n\n")
+		);
+	}
+
 	BackupDialog backup_dialog(this);
 	if (backup_dialog.exec() == QDialog::Accepted)
 	{
diff --git a/sources/utils/qetutils.cpp b/sources/utils/qetutils.cpp
index 8cf457a67..6abbbc4f2 100644
--- a/sources/utils/qetutils.cpp
+++ b/sources/utils/qetutils.cpp
@@ -153,6 +153,12 @@ void QETUtils::pixelSizedFont(QFont &font)
 
 namespace
 {
+	/* Counters for fontFromString(), reset per project load so the editor
+	 * can report how many stored font descriptions needed salvaging or were
+	 * unreadable. Font parsing only happens on the main thread. */
+	int salvaged_font_count = 0;
+	int unreadable_font_count = 0;
+
 	/**
 	 * Legacy (Qt 5) weight <- OpenType weight, closest match,
 	 * same table Qt uses when parsing a 10/11 field string.
@@ -235,6 +241,10 @@ QString QETUtils::fontToString(const QFont &font)
  */
 bool QETUtils::fontFromString(QFont &font, const QString &description)
 {
+	if (description.trimmed().isEmpty()) {
+		return false;
+	}
+
 	QFont parsed(font);
 	if (parsed.fromString(description)) {
 		font = parsed;
@@ -271,8 +281,10 @@ bool QETUtils::fontFromString(QFont &font, const QString &description)
 
 		if (parsed.fromString(legacy)) {
 			font = parsed;
+			++salvaged_font_count;
 			return true;
 		}
+		++unreadable_font_count;
 		return false;
 	}
 
@@ -284,7 +296,50 @@ bool QETUtils::fontFromString(QFont &font, const QString &description)
 	if (count > 11
 		&& parsed.fromString(QStringList(l.mid(0, 11)).join(comma))) {
 		font = parsed;
+		++salvaged_font_count;
 		return true;
 	}
+	++unreadable_font_count;
 	return false;
 }
+
+/**
+ * @brief QETUtils::FontRestorationScope::FontRestorationScope
+ * Open a fresh counting window: the enclosing window's counts are kept
+ * aside and restored by the destructor, so a project load nested inside
+ * another one (through the event loop) reports its own numbers only.
+ */
+QETUtils::FontRestorationScope::FontRestorationScope() :
+	m_outer_salvaged(salvaged_font_count),
+	m_outer_unreadable(unreadable_font_count)
+{
+	salvaged_font_count = 0;
+	unreadable_font_count = 0;
+}
+
+QETUtils::FontRestorationScope::~FontRestorationScope()
+{
+	salvaged_font_count = m_outer_salvaged;
+	unreadable_font_count = m_outer_unreadable;
+}
+
+/**
+ * @brief QETUtils::FontRestorationScope::salvaged
+ * @return How many font descriptions fontFromString() restored from a
+ * foreign or corrupt format since this window was opened. Such descriptions
+ * are rewritten in the stable format on the next save.
+ */
+int QETUtils::FontRestorationScope::salvaged() const
+{
+	return salvaged_font_count;
+}
+
+/**
+ * @brief QETUtils::FontRestorationScope::unreadable
+ * @return How many font descriptions fontFromString() could not restore at
+ * all since this window was opened (the caller's default font applies).
+ */
+int QETUtils::FontRestorationScope::unreadable() const
+{
+	return unreadable_font_count;
+}
diff --git a/sources/utils/qetutils.h b/sources/utils/qetutils.h
index 81872ce41..86fef778b 100644
--- a/sources/utils/qetutils.h
+++ b/sources/utils/qetutils.h
@@ -35,6 +35,29 @@ namespace QETUtils
     QString fontToString (const QFont &font);
     bool fontFromString (QFont &font, const QString &description);
 
+	/**
+		RAII counting window for the font descriptions fontFromString()
+		salvages or fails to read: construction opens a fresh window, the
+		destructor restores the enclosing one. Windows nest strictly LIFO,
+		which covers project loads re-entered through the event loop
+		(DialogWaiting pumps it while the folios are built).
+	*/
+	class FontRestorationScope
+	{
+		public:
+			FontRestorationScope();
+			~FontRestorationScope();
+			FontRestorationScope(const FontRestorationScope &) = delete;
+			FontRestorationScope &operator=(const FontRestorationScope &) = delete;
+
+			int salvaged() const;
+			int unreadable() const;
+
+		private:
+			int m_outer_salvaged;
+			int m_outer_unreadable;
+	};
+
 	bool sortBeginIntString(const QString &str_a, const QString &str_b);
 
 	template <typename T>