Text to Speech by Panopreter от Panopreter Tech

Text-to-Speech add-on by Panopreter is an easy to use tool to read the web page content out. Just click on the pop up menu, the selected text or all the text on the page will be read out with natural sounding voices installed on your Windows computer, the speech synthesis occurs locally on your computer and the text is never sent to the internet. Users can pause or resume the speech, adjust the volume and speed of the speech.

Here is the detail for installing the text to speech add-on for Firefox: https://www.panopreter.com/en/products/panopreter/browser-extension.php