How to fix a footer minipage at the bottom of a page without using of e.g. "fancyhdr"?

Question

I've to fix a footer minipage on one page at the bottom of that page without using of e.g. fancyhdr so that the floating text is breaking into new page when that footer is reached. How to do that? Many thanks in advance.

UPDATE (2021-09-25)

The volume of the beginning text at page 1 is not static. It is dynamically given by another program. It can be 130 words long but also 1,000 or so. So a {figure}[b] at page 1 is no option here because the text may move this figure to page 2 when the volume of the text is big enough.

The text is floating into new page because the minipage is reached but the minipage keeps at this position:

Answer 1

You can use a bottom float. THIS IS AN EDITED VERSION OF MY ORIGINAL ANSWER

% botprob.tex  SE 616534
\documentclass{article}
\usepackage{lipsum}
%\setlength{\textheight}{0.4\textheight}
%%% EDITED RESPONSE
\begin{document}
\begin{figure}[b]
\fbox{At the bottom of the page.}
\end{figure}
\lipsum[1-5]
\end{document}
% ORIGINAL RESPONSE
\begin{document}
\lipsum[1]
\begin{figure}[b]
\fbox{At the bottom of the page.}
\end{figure}
\lipsum[2-3]
\end{document}
\begin{figure}
A FIGURE.
\caption{A fig}
\end{figure}
\end{document}

Answer 2

It's a bit overkill, but easy to implement.

\documentclass{article}
\usepackage{float}
\floatstyle{boxed}
\newfloat{Message}{b}{lom}% \message already used
\usepackage{lipsum}
\begin{document}
\lipsum[1]
\begin{Message} 
  Hello World!
\end{Message}
\lipsum[2-6]
\end{document}

---

This version takes more work but gives more control over the spacing (\textfloatsep).

\documentclass{article}
\usepackage{newfloat}
\DeclareFloatingEnvironment[placement=b,fileext=lom]{floatmsg}
\newsavebox{\messagebox}
\newenvironment{Message}{\floatmsg\vskip-\textfloatsep
  \begin{lrbox}{\messagebox}\minipage{\dimexpr \linewidth-2\fboxsep-2\fboxrule}}%
{\endminipage\end{lrbox}\fbox{\box\messagebox}\endfloatmsg}
\usepackage{lipsum}
\begin{document}
\lipsum[1]
\begin{Message} 
  Hello World!
\end{Message}
\lipsum[2-6]
\end{document}