diff --git a/src/base/path.cpp b/src/base/path.cpp
index dee1c50c4..66270154c 100644
--- a/src/base/path.cpp
+++ b/src/base/path.cpp
@@ -218,6 +218,15 @@ QString Path::toString() const
     return QDir::toNativeSeparators(m_pathStr);
 }
 
+std::filesystem::path Path::toStdFsPath() const
+{
+#ifdef Q_OS_WIN
+    return {data().toStdWString(), std::filesystem::path::format::generic_format};
+#else
+    return {data().toStdString(), std::filesystem::path::format::generic_format};
+#endif
+}
+
 Path &Path::operator/=(const Path &other)
 {
     *this = *this / other;
diff --git a/src/base/path.h b/src/base/path.h
index 6fbb94604..1b9e95198 100644
--- a/src/base/path.h
+++ b/src/base/path.h
@@ -29,6 +29,8 @@
 
 #pragma once
 
+#include <filesystem>
+
 #include <QtGlobal>
 #include <QMetaType>
 #include <QString>
@@ -69,6 +71,7 @@ public:
 
     QString data() const;
     QString toString() const override;
+    std::filesystem::path toStdFsPath() const;
 
     Path &operator/=(const Path &other);
     Path &operator+=(QStringView str);
diff --git a/src/base/utils/fs.cpp b/src/base/utils/fs.cpp
index 044b7d54d..ae0ed75ee 100644
--- a/src/base/utils/fs.cpp
+++ b/src/base/utils/fs.cpp
@@ -31,6 +31,7 @@
 
 #include <cerrno>
 #include <cstring>
+#include <filesystem>
 
 #if defined(Q_OS_WIN)
 #include <memory>
@@ -57,8 +58,8 @@
 #include <QDirIterator>
 #include <QFile>
 #include <QFileInfo>
-#include <QStorageInfo>
 #include <QRegularExpression>
+#include <QStorageInfo>
 
 #include "base/global.h"
 #include "base/path.h"
@@ -161,15 +162,23 @@ qint64 Utils::Fs::computePathSize(const Path &path)
 
 /**
  * Makes deep comparison of two files to make sure they are identical.
+ * The point is about the file contents. If the files do not exist then
+ * the paths refers to nothing and therefore we cannot say the files are same
+ * (because there are no files!)
  */
 bool Utils::Fs::sameFiles(const Path &path1, const Path &path2)
 {
     QFile f1 {path1.data()};
     QFile f2 {path2.data()};
-    if (!f1.exists() || !f2.exists()) return false;
-    if (f1.size() != f2.size()) return false;
-    if (!f1.open(QIODevice::ReadOnly)) return false;
-    if (!f2.open(QIODevice::ReadOnly)) return false;
+
+    if (!f1.exists() || !f2.exists())
+        return false;
+    if (path1 == path2)
+        return true;
+    if (f1.size() != f2.size())
+        return false;
+    if (!f1.open(QIODevice::ReadOnly) || !f2.open(QIODevice::ReadOnly))
+        return false;
 
     const int readSize = 1024 * 1024;  // 1 MiB
     while (!f1.atEnd() && !f2.atEnd())
@@ -214,17 +223,8 @@ Path Utils::Fs::tempPath()
 
 bool Utils::Fs::isRegularFile(const Path &path)
 {
-    struct ::stat st;
-    if (::stat(path.toString().toUtf8().constData(), &st) != 0)
-    {
-        //  analyse erno and log the error
-        const auto err = errno;
-        qDebug("Could not get file stats for path '%s'. Error: %s"
-               , qUtf8Printable(path.toString()), strerror(err));
-        return false;
-    }
-
-    return (st.st_mode & S_IFMT) == S_IFREG;
+    std::error_code ec;
+    return std::filesystem::is_regular_file(path.toStdFsPath(), ec);
 }
 
 bool Utils::Fs::isNetworkFileSystem(const Path &path)
diff --git a/src/gui/addnewtorrentdialog.cpp b/src/gui/addnewtorrentdialog.cpp
index bf300e987..5d682e28a 100644
--- a/src/gui/addnewtorrentdialog.cpp
+++ b/src/gui/addnewtorrentdialog.cpp
@@ -135,6 +135,22 @@ namespace
         return -1;
     }
 
+    qint64 queryFreeDiskSpace(const Path &path)
+    {
+        const Path root = path.rootItem();
+        Path current = path;
+        qint64 freeSpace = Utils::Fs::freeDiskSpaceOnPath(current);
+
+        // for non-existent directories (which will be created on demand) `Utils::Fs::freeDiskSpaceOnPath`
+        // will return invalid value so instead query its parent/ancestor paths
+        while ((freeSpace < 0) && (current != root))
+        {
+            current = current.parentPath();
+            freeSpace = Utils::Fs::freeDiskSpaceOnPath(current);
+        }
+        return freeSpace;
+    }
+
     void setPath(FileSystemPathComboEdit *fsPathEdit, const Path &newPath)
     {
         int existingIndex = indexOfPath(fsPathEdit, newPath);
@@ -530,9 +546,10 @@ void AddNewTorrentDialog::updateDiskSpaceLabel()
         }
     }
 
+    const QString freeSpace = Utils::Misc::friendlyUnit(queryFreeDiskSpace(m_ui->savePath->selectedPath()));
     const QString sizeString = tr("%1 (Free space on disk: %2)").arg(
         ((torrentSize > 0) ? Utils::Misc::friendlyUnit(torrentSize) : tr("Not available", "This size is unavailable."))
-        , Utils::Misc::friendlyUnit(Utils::Fs::freeDiskSpaceOnPath(m_ui->savePath->selectedPath())));
+        , freeSpace);
     m_ui->labelSizeData->setText(sizeString);
 }
 
diff --git a/src/webui/webapplication.cpp b/src/webui/webapplication.cpp
index af2bee65a..bc161e17e 100644
--- a/src/webui/webapplication.cpp
+++ b/src/webui/webapplication.cpp
@@ -165,14 +165,12 @@ void WebApplication::sendWebUIFile()
 
     if (m_isAltUIUsed)
     {
-#ifdef Q_OS_UNIX
         if (!Utils::Fs::isRegularFile(localPath))
         {
             status(500, u"Internal Server Error"_qs);
             print(tr("Unacceptable file type, only regular file is allowed."), Http::CONTENT_TYPE_TXT);
             return;
         }
-#endif
 
         QFileInfo fileInfo {localPath.data()};
         while (Path(fileInfo.filePath()) != m_rootFolder)