I have tried many ways( all documented procedures)to inject script into a specific page upon checking URL at onUpdated.addListener. Finally the below code with \'executescri
UPDATE: Finally figured out your problem. In eventPage.js, you tried to inject js/Leoscript.js, which is NOT whitelisted, instead of js/LeoScript.js (with a capital 'S'), which is whitelisted. Note that URLs are case-sensitive!
chrome.tabs.executeScript(tabId, {file: 'js/LeoScript.js'});
LeoScript.js:
alert('injected');
document.getElementById('username').value='aaaaaaa';