diff --git a/src/libs/utils/completinglineedit.cpp b/src/libs/utils/completinglineedit.cpp
index 4711ee8e721..1e4152ad087 100644
--- a/src/libs/utils/completinglineedit.cpp
+++ b/src/libs/utils/completinglineedit.cpp
@@ -58,8 +58,10 @@ void CompletingLineEdit::keyPressEvent(QKeyEvent *e)
 {
     if (e->key() == Qt::Key_Down && !e->modifiers()) {
         if (QCompleter *comp = completer()) {
-            if (!comp->popup()->isVisible())
+            if (!comp->popup()->isVisible()) {
                 comp->complete();
+                return;
+            }
         }
     }
     QLineEdit::keyPressEvent(e);
diff --git a/src/libs/utils/delegates.cpp b/src/libs/utils/delegates.cpp
index 6b6ab7279ef..a677c8c9923 100644
--- a/src/libs/utils/delegates.cpp
+++ b/src/libs/utils/delegates.cpp
@@ -24,9 +24,11 @@
 ****************************************************************************/
 
 #include "delegates.h"
+#include "completinglineedit.h"
 
 #include <QPainter>
 #include <QApplication>
+#include <QCompleter>
 
 using namespace Utils;
 
@@ -174,3 +176,60 @@ void PathChooserDelegate::setHistoryCompleter(const QString &key)
 {
     m_historyKey = key;
 }
+
+CompleterDelegate::CompleterDelegate(const QStringList &candidates, QObject *parent)
+    : CompleterDelegate(new QCompleter(candidates, parent))
+{ }
+
+CompleterDelegate::CompleterDelegate(QAbstractItemModel *model, QObject *parent)
+    : CompleterDelegate(new QCompleter(model, parent))
+{ }
+
+CompleterDelegate::CompleterDelegate(QCompleter *completer, QObject *parent)
+    : QStyledItemDelegate(parent)
+    , m_completer(completer)
+{ }
+
+CompleterDelegate::~CompleterDelegate()
+{
+    if (m_completer)
+        delete m_completer;
+}
+
+QWidget *CompleterDelegate::createEditor(QWidget *parent,
+                                         const QStyleOptionViewItem &option,
+                                         const QModelIndex &index) const
+{
+    Q_UNUSED(option);
+    Q_UNUSED(index);
+
+    auto edit = new CompletingLineEdit(parent);
+
+    edit->setCompleter(m_completer);
+
+    return edit;
+}
+
+void CompleterDelegate::setEditorData(QWidget *editor,
+                                      const QModelIndex &index) const
+{
+    if (auto *edit = qobject_cast<CompletingLineEdit *>(editor))
+        edit->setText(index.model()->data(index, Qt::EditRole).toString());
+}
+
+void CompleterDelegate::setModelData(QWidget *editor,
+                                     QAbstractItemModel *model,
+                                     const QModelIndex &index) const
+{
+    if (auto edit = qobject_cast<CompletingLineEdit *>(editor))
+        model->setData(index, edit->text(), Qt::EditRole);
+}
+
+void CompleterDelegate::updateEditorGeometry(QWidget *editor,
+                                             const QStyleOptionViewItem &option,
+                                             const QModelIndex &index) const
+{
+    Q_UNUSED(index);
+
+    editor->setGeometry(option.rect);
+}
diff --git a/src/libs/utils/delegates.h b/src/libs/utils/delegates.h
index cb9809a36f4..eb9819fc7ab 100644
--- a/src/libs/utils/delegates.h
+++ b/src/libs/utils/delegates.h
@@ -81,4 +81,30 @@ private:
     QString m_historyKey;
 };
 
+class QTCREATOR_UTILS_EXPORT CompleterDelegate : public QStyledItemDelegate
+{
+public:
+    CompleterDelegate(const QStringList &candidates, QObject *parent = nullptr);
+    CompleterDelegate(QAbstractItemModel *model, QObject *parent = nullptr);
+    CompleterDelegate(QCompleter *completer, QObject *parent = nullptr);
+    ~CompleterDelegate() override;
+
+    CompleterDelegate(const CompleterDelegate &other) = delete;
+    CompleterDelegate(CompleterDelegate &&other) = delete;
+
+    CompleterDelegate &operator=(const CompleterDelegate &other) = delete;
+    CompleterDelegate &operator=(CompleterDelegate &&other) = delete;
+
+    QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
+                          const QModelIndex &index) const override;
+    void setEditorData(QWidget *editor, const QModelIndex &index) const override;
+    void setModelData(QWidget *editor, QAbstractItemModel *model,
+                      const QModelIndex &index) const override;
+    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const
+                              QModelIndex &index) const override;
+
+private:
+    QCompleter *m_completer = nullptr;
+};
+
 } // Utils
diff --git a/src/plugins/languageclient/baseclient.cpp b/src/plugins/languageclient/baseclient.cpp
index 3bac57b2b2d..3c5569266cb 100644
--- a/src/plugins/languageclient/baseclient.cpp
+++ b/src/plugins/languageclient/baseclient.cpp
@@ -114,8 +114,7 @@ BaseClient::State BaseClient::state() const
 void BaseClient::openDocument(Core::IDocument *document)
 {
     using namespace TextEditor;
-    const QString languageId = TextDocumentItem::mimeTypeToLanguageId(document->mimeType());
-    if (!isSupportedLanguage(languageId))
+    if (!isSupportedMimeType(document->mimeType()))
         return;
     const FileName &filePath = document->filePath();
     const QString method(DidOpenTextDocumentNotification::methodName);
@@ -137,7 +136,7 @@ void BaseClient::openDocument(Core::IDocument *document)
     }
     auto textDocument = qobject_cast<TextDocument *>(document);
     TextDocumentItem item;
-    item.setLanguageId(languageId);
+    item.setLanguageId(TextDocumentItem::mimeTypeToLanguageId(document->mimeType()));
     item.setUri(DocumentUri::fromFileName(filePath));
     item.setText(QString::fromUtf8(document->contents()));
     item.setVersion(textDocument ? textDocument->document()->revision() : 0);
@@ -483,14 +482,14 @@ void BaseClient::projectClosed(ProjectExplorer::Project *project)
     sendContent(change);
 }
 
-void BaseClient::setSupportedLanguages(const QStringList &supportedLanguages)
+void BaseClient::setSupportedMimeType(const QStringList &supportedMimeTypes)
 {
-    m_supportedLanguageIds = supportedLanguages;
+    m_supportedMimeTypes = supportedMimeTypes;
 }
 
-bool BaseClient::isSupportedLanguage(const QString &language) const
+bool BaseClient::isSupportedMimeType(const QString &mimeType) const
 {
-    return m_supportedLanguageIds.isEmpty() || m_supportedLanguageIds.contains(language);
+    return m_supportedMimeTypes.isEmpty() || m_supportedMimeTypes.contains(mimeType);
 }
 
 void BaseClient::reset()
diff --git a/src/plugins/languageclient/baseclient.h b/src/plugins/languageclient/baseclient.h
index 211b4b7a157..e0626bd7c78 100644
--- a/src/plugins/languageclient/baseclient.h
+++ b/src/plugins/languageclient/baseclient.h
@@ -104,8 +104,8 @@ public:
                      const LanguageServerProtocol::IContent &content);
     void cancelRequest(const LanguageServerProtocol::MessageId &id);
 
-    void setSupportedLanguages(const QStringList &supportedLanguages);
-    bool isSupportedLanguage(const QString &language) const;
+    void setSupportedMimeType(const QStringList &supportedMimeTypes);
+    bool isSupportedMimeType(const QString &mimeType) const;
 
     void setName(const QString &name) { m_displayName = name; }
     QString name() const { return m_displayName; }
@@ -149,7 +149,7 @@ private:
     QHash<QByteArray, ContentHandler> m_contentHandler;
     QBuffer m_buffer;
     QString m_displayName;
-    QStringList m_supportedLanguageIds;
+    QStringList m_supportedMimeTypes;
     QList<Utils::FileName> m_openedDocument;
     Core::Id m_id;
     LanguageServerProtocol::ServerCapabilities m_serverCapabilities;
diff --git a/src/plugins/languageclient/languageclientsettings.cpp b/src/plugins/languageclient/languageclientsettings.cpp
index e1470edf05a..f2ee17ffc2a 100644
--- a/src/plugins/languageclient/languageclientsettings.cpp
+++ b/src/plugins/languageclient/languageclientsettings.cpp
@@ -30,10 +30,12 @@
 #include <coreplugin/icore.h>
 #include <utils/algorithm.h>
 #include <utils/delegates.h>
+#include <utils/mimetypes/mimedatabase.h>
 #include <languageserverprotocol/lsptypes.h>
 
 #include <QBoxLayout>
 #include <QComboBox>
+#include <QCompleter>
 #include <QCoreApplication>
 #include <QFileInfo>
 #include <QHeaderView>
@@ -44,7 +46,7 @@
 
 constexpr char nameKey[] = "name";
 constexpr char enabledKey[] = "enabled";
-constexpr char languageKey[] = "language";
+constexpr char mimeTypeKey[] = "mimeType";
 constexpr char executableKey[] = "executable";
 constexpr char argumentsKey[] = "arguments";
 constexpr char settingsGroupKey[] = "LanguageClient";
@@ -75,7 +77,7 @@ public:
     enum Columns {
         DisplayNameColumn = 0,
         EnabledColumn,
-        LanguageColumn,
+        MimeTypeColumn,
         ExecutableColumn,
         ArgumentsColumn,
         ColumnCount
@@ -152,7 +154,14 @@ LanguageClientSettingsPageWidget::LanguageClientSettingsPageWidget(LanguageClien
     m_view->header()->setStretchLastSection(true);
     m_view->setRootIsDecorated(false);
     m_view->setItemsExpandable(false);
-    m_view->setItemDelegateForColumn(LanguageClientSettingsModel::LanguageColumn, new LanguageChooseDelegate());
+    auto mimeTypes = Utils::transform(Utils::allMimeTypes(), [](const Utils::MimeType &mimeType){
+        return mimeType.name();
+    });
+    auto mimeTypeCompleter = new QCompleter(mimeTypes);
+    mimeTypeCompleter->setCaseSensitivity(Qt::CaseInsensitive);
+    mimeTypeCompleter->setFilterMode(Qt::MatchContains);
+    m_view->setItemDelegateForColumn(LanguageClientSettingsModel::MimeTypeColumn,
+                                     new Utils::CompleterDelegate(mimeTypeCompleter));
     auto executableDelegate = new Utils::PathChooserDelegate();
     executableDelegate->setExpectedKind(Utils::PathChooser::File);
     executableDelegate->setHistoryCompleter("LanguageClient.ServerPathHistory");
@@ -232,7 +241,7 @@ QVariant LanguageClientSettingsModel::data(const QModelIndex &index, int role) c
     if (role == Qt::DisplayRole || role == Qt::EditRole) {
         switch (index.column()) {
         case DisplayNameColumn: return setting.m_name;
-        case LanguageColumn: return setting.m_language;
+        case MimeTypeColumn: return setting.m_mimeType;
         case ExecutableColumn: return setting.m_executable;
         case ArgumentsColumn: return setting.m_arguments.join(' ');
         }
@@ -250,7 +259,7 @@ QVariant LanguageClientSettingsModel::headerData(int section, Qt::Orientation or
     switch (section) {
     case DisplayNameColumn: return tr("Name");
     case EnabledColumn: return tr("Enabled");
-    case LanguageColumn: return tr("Language");
+    case MimeTypeColumn: return tr("Mime Type");
     case ExecutableColumn: return tr("Executable");
     case ArgumentsColumn: return tr("Arguments");
     }
@@ -288,7 +297,7 @@ bool LanguageClientSettingsModel::setData(const QModelIndex &index, const QVaria
     if (role == Qt::DisplayRole || role == Qt::EditRole) {
         switch (index.column()) {
         case DisplayNameColumn: setting.m_name = value.toString(); break;
-        case LanguageColumn: setting.m_language = value.toString(); break;
+        case MimeTypeColumn: setting.m_mimeType = value.toString(); break;
         case ExecutableColumn: setting.m_executable = value.toString(); break;
         case ArgumentsColumn: setting.m_arguments = value.toString().split(' '); break;
         default:
@@ -346,8 +355,8 @@ void LanguageClientSettingsModel::applyChanges()
         });
         if (setting.isValid() && setting.m_enabled) {
             toStart.removeAll(setting);
-            if (!interface->isSupportedLanguage(setting.m_language))
-                interface->setSupportedLanguages({setting.m_language});
+            if (!interface->isSupportedMimeType(setting.m_mimeType))
+                interface->setSupportedMimeType({setting.m_mimeType});
         } else {
             toShutdown << interface;
         }
@@ -358,8 +367,8 @@ void LanguageClientSettingsModel::applyChanges()
         if (setting.isValid() && setting.m_enabled) {
             auto client = new StdIOClient(setting.m_executable, setting.m_arguments);
             client->setName(setting.m_name);
-            if (setting.m_language != noLanguageFilter)
-                client->setSupportedLanguages({setting.m_language});
+            if (setting.m_mimeType != noLanguageFilter)
+                client->setSupportedMimeType({setting.m_mimeType});
             LanguageClientManager::startClient(client);
         }
     }
@@ -374,7 +383,7 @@ bool LanguageClientSettings::operator==(const LanguageClientSettings &other) con
 {
     return m_name == other.m_name
             && m_enabled == other.m_enabled
-            && m_language == other.m_language
+            && m_mimeType == other.m_mimeType
             && m_executable == other.m_executable
             && m_arguments == other.m_arguments;
 }
@@ -384,7 +393,7 @@ QVariantMap LanguageClientSettings::toMap() const
     QVariantMap map;
     map.insert(nameKey, m_name);
     map.insert(enabledKey, m_enabled);
-    map.insert(languageKey, m_language);
+    map.insert(mimeTypeKey, m_mimeType);
     map.insert(executableKey, m_executable);
     map.insert(argumentsKey, m_arguments);
     return map;
@@ -394,7 +403,7 @@ LanguageClientSettings LanguageClientSettings::fromMap(const QVariantMap &map)
 {
     return { map[nameKey].toString(),
                 map[enabledKey].toBool(),
-                map[languageKey].toString(),
+                map[mimeTypeKey].toString(),
                 map[executableKey].toString(),
                 map[argumentsKey].toStringList() };
 }
diff --git a/src/plugins/languageclient/languageclientsettings.h b/src/plugins/languageclient/languageclientsettings.h
index d06481e7632..cefcd0f2c7c 100644
--- a/src/plugins/languageclient/languageclientsettings.h
+++ b/src/plugins/languageclient/languageclientsettings.h
@@ -39,17 +39,17 @@ class LanguageClientSettings
 {
 public:
     LanguageClientSettings() = default;
-    LanguageClientSettings(const QString &name, bool enabled, const QString &language,
+    LanguageClientSettings(const QString &name, bool enabled, const QString &mimeTypeName,
                            const QString &executable, const QStringList &arguments)
         : m_name(name)
         , m_enabled(enabled)
-        , m_language(language)
+        , m_mimeType(mimeTypeName)
         , m_executable(executable)
         , m_arguments(arguments)
     {}
     QString m_name = QString("New Language Server");
     bool m_enabled = true;
-    QString m_language = QLatin1String(noLanguageFilter);
+    QString m_mimeType = QLatin1String(noLanguageFilter);
     QString m_executable;
     QStringList m_arguments;