While regular gameplay you got a floppy disk symbol on the top right, once you click it you get a huge number of characters (for me it is around 4k characters).
You need to save this (use the copy text button on the bottom right to copy the text with one click) and store it in a file (I personally copy it into a windows editor file.
Once a new update comes out for the game you can paste this text into the "PASSWORD" screen in the main menu.