Change font size of thebibliography environment for article documentclass

Question

I would like to use a smaller font size for thebibliography environment.

After reading the answers to the question What font size is used in the 'thebibliography' environment? I learned that the font size can be changed with the directive:

\renewcommand{\bibliofont}{<desired font size>}

Unfortunately, this does not seem to work with my document.

The only significant differences with respect to the other question is that I am using the article documentclass instead of amsart and that I am using Overleaf to compose my document.

What am I missing?

---

Minimal Working Example:

\documentclass[12pt,english]{article}

\usepackage[utf8]{inputenc}
\usepackage{lmodern}
\usepackage[a4paper, hmargin=2cm, bmargin=3cm, tmargin=4cm, centering]{geometry}
\usepackage[colorlinks,allcolors=blue]{hyperref}
\usepackage{cleveref}

\newcommand{\bibliofont}{\tiny} % <-- THIS DOES NOT WORK!

\begin{document}

    This is an example, more information here~\cite{bib1} and here~\cite{bib2}.\\

    \begin{thebibliography}{1}
        \bibitem{bib1}
        \url{https://example.com/}

        \bibitem{bib2}
        \url{https://example.net/}
    \end{thebibliography}

\end{document}\grid

Answer 1

\bibliofont is not available in all document classes. It seems to be specific to amsart.

You could try

  {\tiny
   \begin{thebibliography}{1}
     \bibitem{bib1}
     \url{https://example.com/}

     \bibitem{bib2}
     \url{https://example.net/}
   \end{thebibliography}}

which is not too pretty code-wise, but should work in most cases (since many classes explicitly set the heading size so that it is unaffected by the \tiny).

---

Other than that you'd have to redefine or patch the definition of thebibliography to include \bibliofont.

\newcommand{\bibliofont}{\tiny}

\makeatletter
    \renewenvironment{thebibliography}[1]
         {\section*{\refname}%
          \@mkboth{\MakeUppercase\refname}{\MakeUppercase\refname}%
          \bibliofont
          \list{\@biblabel{\@arabic\c@enumiv}}%
               {\settowidth\labelwidth{\@biblabel{#1}}%
                \leftmargin\labelwidth
                \advance\leftmargin\labelsep
                \@openbib@code
                \usecounter{enumiv}%
                \let\p@enumiv\@empty
                \renewcommand\theenumiv{\@arabic\c@enumiv}}%
          \sloppy
          \clubpenalty4000
          \@clubpenalty \clubpenalty
          \widowpenalty4000%
          \sfcode`\.\@m}
         {\def\@noitemerr
           {\@latex@warning{Empty `thebibliography' environment}}%
          \endlist}
\makeatother

That would be prettier because it executes the size command in the right place, but it also requires knowledge of the original definition of thebibliography.