inject-cs

Inject is the Action that Injects javascript code into content script during project workflow, also you can use Jquery. It uses javascript eval() function to inject your code. so here you can write your javascript code using functions and variables, just notice only one thing that extensions create contect script for each Iframe.

$("body").html("Hello World");

async/await

You can also use async/await in the cs-inject that way you can wait for an async function execution before proceeding with the next action.

await new Promise((resolve) => {
  setTimeout(() => {
    resolve();
  }, 300);
});