By any chance, is it a PDF-based form? Firefox's built-in PDF Viewer doesn't support PDF form features completely. You might need to switch to using the Adobe plugin. This article has the steps for that: View and edit PDF files using Firefox’s built-in viewer.

If it's an ordinary web form, is this a page someone could view without an account? You could post the URL here for a volunteer to test.

It is not a pdf. The initial page is https://www.linklearncertification.com/d/. On the right side of the page is a "Practice Lab" link. At this moment it seems to being maintained so is not accessible at all. It should be back up by Monday. The problem is that when entries are made on a page they do not actually update the database. The screen "blinks" like something is happening but the return is unchanged. I have IE but people using an Apple and Firefox cannot use the site with firefox.

You may have to allow all cookies if you currently block all or some third-party cookies.

• Tools > Options > Privacy > Firefox will: "Use custom settings for history"

You can also check the Web Console and Browser Console (Firefox/Tools > Web Developer) for errors.

I will try again and check the tools. Most users of the IRS tax training sites seem to have difficulty with any browser but IE. Is there anything unique to IE that would cause Firefox to not work?

Hi nclarkca, I can't get past the login page, but I can see from that page that it is an ASP.Net site. Microsoft has regularly updated its core .Net technology with more advanced features and improved compatibility with other browsers, but the .Net ecosystem includes a lot of third party components that may not work well with other browsers. I don't think I can say much more without getting access to the system.