Announcement capability

I’d like a place where I can enter an annmouncement that will be displayed at the top of the page where it will be easily seen. I know I can add it manually to the DataHTM3.txt file without it being overwritten, but that would put it way at the bottom of the page.

Is this already possible and I just don’t know about it?

add it to the end of the datahtm0.txt file