[MC-168867] "Merry X-mas!" splash text does not appear on December 25 and 26

The Bug
The Merry X-Mas Splash Text is not showing despite it still being in the time frame of December 24-26.

Code Analysis
See code analysis by @unknown in this comment

Note
This post was made on December 26 2019

Attachments

if (calendar2.get(2) + 1 == 12 && calendar2.get(5) == 24) {
   return "Merry X-mas!";
}

According to the code, this splash text only shows on Dec. 24 ^th. This might be intended.

I was able to reproduce this in Christmas. This didn't happen at 2018 Christmas. (1.13.2)

I can confirm it does affect 1.20.4 so please add

Can confirm in 1.21.4.