Tips

- Bypass caching
  When injecting link element for css file, the problem of caching can be annoying so append something in the url like this
  ```js
	// Create a link element for the CSS file
	const linkElement = document.createElement('link');
	linkElement.rel = 'stylesheet';
	linkElement.href = browser.runtime.getURL('styles.css') + '?v=' + Date.now(); // Append a timestamp
	document.head.appendChild(linkElement);

	```
- Reset injected element
  When we inject DOM element and reload extension previous one wont get removed unless page is reloaded so tag all those inserted element with extension name or by adding it in class.
  `contentScript.js`
  ```js
	
	// removing elements of class of ext_name
	function reset1(){

	 	const elements=document.querySelectorAll(`.${ext_name}`)

	 	for(let ele of elements){
	 		ele.remove()
	 	}


	 }

	 reset1();

	const navibar= document.createElement("div")
	navibar.className=`${ext_name} navigation_bar`
	navibar.innerHTML=`
		<button class=" nav_btn"> All Replies </button>
	`

	
	console.log('navibar: ',navibar.outerHTML);


	
	const app=document.querySelector("body")
	app.insertBefore(navibar, app.children[0])

	```
&nbsp;

in firefox to allow custom extensions for permanent without uploading in firefox

Type `about:config` in the address bar and press Enter
Search for `xpinstall.signatures.required`.
Ensure the value is set to false (toggle it by double-clicking if necessary).