How to record this simple Macro on Microsoft Edge Browser (or any browser)?

I am a new user and I am having a problem with recording this kind of Macro!
What I want to do is the following:
I already have this web page opened: math (
It allows me to draw/write maths equations and then copy them as MathML or LaTeX which is really helpful.
Here is the problem: on that link (without drawing anything yet) I start recording the Macro by clicking on the “MathML” button and then the “Copy” button (both on the right). I stop recording and save the Macro. I write down the equation and Play the Macro but what happens is that it “copies” me not what I just wrote but what I had copied at the moment of recording the Macro (i.e. Nothing!).

To make it clear here is an example:
To record the Macro I write down “X+3”, the Macro consists of clicking MathML button then Copy button. Then when I change and write “Y+5” instead, and execute/play the recorded Macro, it still copies me X+3 (and not the last thing I wrote).

Is there any way to solve this?
I heard about a waiting function, something like Click on MathML + wait for 10 seconds (until I write down what I want) + Copy! it will work, but it is not what I am looking for! I just want the Macro to copy on clipboard the last thing on the page and not what it memorized at the moment of recording!

Please give me detailed instructions! :pray: (I am using the Browser extension - free version).

Finally (but that is a different question), is there any way to “launch” (play) that Macro Script with a Hotkey (a keyboard shorcut) directly on the Browser? It will save me so much time. (I just want to use the Mouse less and less. it is the main reason, as many people, I decided to get into Automation/Macro tools! I want to make my user experience and workflows more efficient!).

Thank you for your help!!