Track enter key hit in a ssrs 2019 report by edge extension

Question

I want to react with an edge extension having a SSRS 2019 report opened in the browser and you are inside an input field and hit enter.

content.js

window.addEventListener('keydown',(event)=>{
chrome.runtime.sendMessage(null,(response)=>{
alert("keydown event");
})
})

Background.js

chrome.runtime.onMessage.addListener((message,sender,sendResponse)=>{
sendResponse("I have received the message!")
})

But as soon as I clicked into the input it won't react at all.
I have just one text and one date input in the report.