how to know if Java is installed on my windows11

Well.. Firefox uses Javascript on websites which only gets updated when Firefox does. You can visit https://www.whatismybrowser.com/detect/is-javascript-enabled/ to see if it's enabled in Firefox. It doesn't cause a popup asking to update Java that I have ever seen.

Sounds like your system might have actual Java installed and that's what is displaying the popup. Difference: https://www.java.com/en/download/help/java_javascript.html.

I'd look in Windows' Control Panel -> Programs & Features to see if it's listed there. Might also find it in Windows' Settings -> Apps.

Hope that helps, Mark H.

The desktop Firefox web browser has not used the NPAPI Java Plugin since Firefox 52.0 Release back on March 7, 2017. https://support.mozilla.org/en-US/kb/npapi-plugins

Note the JavaScript in Firefox and the Java Plugin are two separate things. JavaScript was originally going to be called LiveScript which would have greatly reduced this confusion. https://kb.mozillazine.org/JavaScript_is_not_Java

MarkRH has already explained the main difference between Java and JavaScript correctly. If you want to confirm whether Java is installed on Windows 11, you can also open Command Prompt and type `java -version`, then press Enter. If Java is installed and configured properly, it will display the installed version. If Windows says the command is not recognized, Java may not be installed or its PATH variable may not be configured correctly.

You can also check Settings > Apps > Installed apps and search for Java to see whether it is listed there.

And if the popup appears every day, I would recommend checking which application is actually displaying it before clicking any update button, especially if you are unsure where it comes from. 🔧

It wouldn't hurt to do some malware scans. See the following article for tools other Firefox users have found helpful: Troubleshoot Firefox issues caused by malware.

Ooo, I that's an idea. Thank you

Thank you, PC does have Java 8- 171 So safe to update.

Thank you

Mark, thank you. this PC does have Java 6-171 (63 bit). I originally had looked under settings but missed the obvious first choice of default apps! Everyone has been so helpful.