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src/kontactplugin/knoteslistwidgetsearchline.cpp

@@ -9,6 +9,32 @@
 
 #include <KLocalizedString>
 
+static QString normalize(QStringView str)
+{
+    QString out;
+    out.reserve(str.size());
+    for (const auto c : str) {
+        // case folding
+        const auto n = c.toCaseFolded();
+
+        // if the character has a canonical decomposition use that and skip the
+        // combining diacritic markers following it
+        // see https://en.wikipedia.org/wiki/Unicode_equivalence
+        // see https://en.wikipedia.org/wiki/Combining_character
+        if (n.decompositionTag() == QChar::Canonical) {
+            out.push_back(n.decomposition().at(0));
+        }
+        // handle compatibility compositions such as ligatures
+        // see https://en.wikipedia.org/wiki/Unicode_compatibility_characters
+        else if (n.decompositionTag() == QChar::Compat && n.isLetter() && n.script() == QChar::Script_Latin) {
+            out.append(n.decomposition());
+        } else {
+            out.push_back(n);
+        }
+    }
+    return out;
+}
+
 KNotesListWidgetSearchLine::KNotesListWidgetSearchLine(QWidget *parent)
     : KListWidgetSearchLine(parent)
 {
@@ -31,10 +57,11 @@ bool KNotesListWidgetSearchLine::itemMatches(const QListWidgetItem *item, const
     if (!iconView) {
         return false;
     }
-    if (iconView->realName().contains(s)) {
+    const QString strNormalize{normalize(s)};
+    if (normalize(iconView->realName()).contains(strNormalize)) {
         return true;
     }
-    if (iconView->description().contains(s)) {
+    if (normalize(iconView->description()).contains(strNormalize)) {
         return true;
     }
     return KListWidgetSearchLine::itemMatches(item, s);