MathJax not rendering after refresh page

In order to understand how MathJax works, I have developed a very basic and simple html file (called test.html) with some MathJax equations:

<html>

    <!-- Module for rendering Markdown content -->
    <script type="module" src="https://md-block.verou.me/md-block.js"></script>

    <!-- Module for rendering mathematical equations -->
    <script id="MathJax-script" async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script>

    <body>
        <md-block>

            Let's solve a simple second-order homogeneous linear differential equation with constant coefficients. One common example is:

            [
            y'' - 5y' + 6y = 0
            ]

            To solve this, we'll find the characteristic equation by assuming a solution of the form ( y = e^{rt} ), where ( r ) is a constant. The derivative terms ( y' ) and ( y'' ) become ( re^{rt} ) and ( r^2e^{rt} ) respectively, leading to the characteristic equation:

            [
            r^2 - 5r + 6 = 0
            ]

            This quadratic can be factored as:

            [
            (r - 2)(r - 3) = 0
            ]

            So, ( r_1 = 2 ) and ( r_2 = 3 ) are the roots. Therefore, the general solution of the differential equation is:

            [
            y(t) = c_1e^{2t} + c_2e^{3t}
            ]

            Here, ( c_1 ) and ( c_2 ) are constants determined by initial conditions, which are not given in this context. Thus, we have the general form of the solution.

        </md-block>
    </body>
</html>

Now, if I open with Google Chrome the test.html file, the equations render perfectly, but when I refresh the page using the refresh button of Chrome, the euqations are shown in their row form. I have to wait around a couple of minutes to have the equations properly rendered in MathJax format.

Do you know what could be the reason and how should I edit this file in order to have a properly working code?