We would like to wish a ‘Wesołych Świąt’ to anyone reading this!
Wesołych Świąt translates directly into English as Happy / Merry Holiday. So it is, perhaps, the equivalent of ‘Seasons Greetings’ in English. It is used equally at Easter and Christmas time in Poland.
However, as it is nearly Christmas we are using the phrase to say and wish all a very Happy Christmas!