See how festive it is? This is the softer side of Hamas!
The Google autotranslate is not 100% accurate. It translates closer to "May you be well every year" and is used as as a standard greeting for annual holidays as well as birthdays. So, for example, this is the same phrase being posted by Hamas at the end of Ramadan this year:
The flowers are a nice touch. It makes the message of "death to Jews" a lot homier.