diff --git a/src/libs/utils/mimetypes2/mimedatabase.cpp b/src/libs/utils/mimetypes2/mimedatabase.cpp
index 8d9fd8a65ca..1bfa175468c 100644
--- a/src/libs/utils/mimetypes2/mimedatabase.cpp
+++ b/src/libs/utils/mimetypes2/mimedatabase.cpp
@@ -45,6 +45,7 @@
 
 #include "mimeprovider_p.h"
 #include "mimetype_p.h"
+#include "mimeutils.h"
 
 #include <QtCore/QFile>
 #include <QtCore/QFileInfo>
@@ -531,6 +532,10 @@ MimeType MimeDatabase::mimeTypeForName(const QString &nameOrAlias) const
 {
     QMutexLocker locker(&d->mutex);
 
+    if (d->m_startupPhase <= int(MimeStartupPhase::PluginsInitializing))
+        qWarning("Accessing MimeDatabase for %s before plugins are initialized",
+                 qPrintable(nameOrAlias));
+
     return d->mimeTypeForName(nameOrAlias);
 }
 
@@ -566,6 +571,10 @@ MimeType MimeDatabase::mimeTypeForFile(const QFileInfo &fileInfo, MatchMode mode
 {
     QMutexLocker locker(&d->mutex);
 
+    if (d->m_startupPhase <= int(MimeStartupPhase::PluginsInitializing))
+        qWarning("Accessing MimeDatabase for %s before plugins are initialized",
+                 qPrintable(fileInfo.filePath()));
+
     if (fileInfo.isDir())
         return d->mimeTypeForName(QLatin1String("inode/directory"));
 
@@ -619,6 +628,11 @@ MimeType MimeDatabase::mimeTypeForFile(const QString &fileName, MatchMode mode)
 {
     if (mode == MatchExtension) {
         QMutexLocker locker(&d->mutex);
+
+        if (d->m_startupPhase <= int(MimeStartupPhase::PluginsInitializing))
+            qWarning("Accessing MimeDatabase for %s before plugins are initialized",
+                     qPrintable(fileName));
+
         const QStringList matches = d->mimeTypeForFileName(fileName);
         const int matchCount = matches.count();
         if (matchCount == 0) {
@@ -652,6 +666,10 @@ QList<MimeType> MimeDatabase::mimeTypesForFileName(const QString &fileName) cons
 {
     QMutexLocker locker(&d->mutex);
 
+    if (d->m_startupPhase <= int(MimeStartupPhase::PluginsInitializing))
+        qWarning("Accessing MimeDatabase for %s before plugins are initialized",
+                 qPrintable(fileName));
+
     const QStringList matches = d->mimeTypeForFileName(fileName);
     QList<MimeType> mimes;
     mimes.reserve(matches.count());
@@ -683,6 +701,9 @@ MimeType MimeDatabase::mimeTypeForData(const QByteArray &data) const
 {
     QMutexLocker locker(&d->mutex);
 
+    if (d->m_startupPhase <= int(MimeStartupPhase::PluginsInitializing))
+        qWarning("Accessing MimeDatabase for data before plugins are initialized");
+
     int accuracy = 0;
     return d->findByData(data, &accuracy);
 }
@@ -812,6 +833,9 @@ QList<MimeType> MimeDatabase::allMimeTypes() const
 {
     QMutexLocker locker(&d->mutex);
 
+    if (d->m_startupPhase <= int(MimeStartupPhase::PluginsInitializing))
+        qWarning("Accessing MimeDatabase for all mime types before plugins are initialized");
+
     return d->allMimeTypes();
 }
 
diff --git a/src/libs/utils/mimetypes2/mimedatabase_p.h b/src/libs/utils/mimetypes2/mimedatabase_p.h
index 69e3020d901..114661a06d7 100644
--- a/src/libs/utils/mimetypes2/mimedatabase_p.h
+++ b/src/libs/utils/mimetypes2/mimedatabase_p.h
@@ -116,6 +116,9 @@ private:
 public:
     const QString m_defaultMimeType;
     QMutex mutex;
+
+    // added for Qt Creator
+    int m_startupPhase = 0;
 };
 
 } // namespace Utils
diff --git a/src/libs/utils/mimetypes2/mimeutils.cpp b/src/libs/utils/mimetypes2/mimeutils.cpp
index 56a2d934771..0340366b440 100644
--- a/src/libs/utils/mimetypes2/mimeutils.cpp
+++ b/src/libs/utils/mimetypes2/mimeutils.cpp
@@ -94,11 +94,14 @@ QList<MimeType> allMimeTypes()
 
 void setMimeStartupPhase(MimeStartupPhase phase)
 {
-    //    auto d = MimeDatabasePrivate::instance();
-    //    QMutexLocker locker(&d->mutex);
-    //    if (int(phase) != d->m_startupPhase + 1)
-    //        qWarning("Unexpected jump in MimedDatabase lifetime from %d to %d", d->m_startupPhase, int(phase));
-    //    d->m_startupPhase = int(phase);
+    auto d = MimeDatabasePrivate::instance();
+    QMutexLocker locker(&d->mutex);
+    if (int(phase) != d->m_startupPhase + 1) {
+        qWarning("Unexpected jump in MimedDatabase lifetime from %d to %d",
+                 d->m_startupPhase,
+                 int(phase));
+    }
+    d->m_startupPhase = int(phase);
 }
 
 void addMimeTypes(const QString &fileName, const QByteArray &data)