Using the native Webflow interactions to move the text elements up and out of the "mask".
To create a "mask" simply wrap all the changing text elements with a div and give it overflow: hidden.
The interaction is a "Page load" interaction, which means that when you copy the elements it will not copy along. To solve this you can apply the interaction temporarily as a "Click interaction" to the element you copy, and after you copy, replace the click interaction with a "Page load" interaction.
Automatically insert the current year to any element with the class of 'year'
Using JS to scroll a div (menu) to the current link inside.