EntityframeworkCore: Local MDF-File in Debug-Folder gets deleted

Question

I'm using EntityframeworkCore with a LocalDB-MDF File.

I'm attaching the MDF in the Datacontext with the following Code. As you can see, the Code is also found at StackOverflow :)

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
    // http://stackoverflow.com/questions/3500829/sql-express-connection-string-mdf-file-location-relative-to-application-locatio
    var mdfFileFullName = Handlers.DatabaseFileHandler.GetLocalMdfFileFullname();
    var connectionString = $@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename={mdfFileFullName};Integrated Security=True";
    optionsBuilder.UseSqlServer(connectionString);
}

And get the MDF just by definining, that it has to be in the Output-Folder:

internal static class DatabaseFileHandler
{
    internal static string GetLocalMdfFileFullname()
    {
        var mdfFilePath = GetAssemblyPath();
        var result = Path.Combine(mdfFilePath, Infrastructure.Constants.DATABASEFILE_NAME);
        return result;
    }

    private static string GetAssemblyPath()
    {
        string codeBase = Assembly.GetExecutingAssembly().CodeBase;
        UriBuilder uri = new UriBuilder(codeBase);
        string result = Uri.UnescapeDataString(uri.Path);
        result = Path.GetDirectoryName(result);

        return result;
    }
}

The MDF-File itself is defined as "Content" and with "Copy if newer".

Now, interesting enough, on some occasions, when I debug my program and stop, on the next startup the MDF is deleted from the Output-Folder.

Unfortunately, I can't even say if the File is deleted when I stop or start the program, since it happens quite rarely.

Interesting enough, this doesn't eve happen, if I clean the solution, so this has to be another Visual Studio mechanism I'm not aware of.