Firefox is a web browser from Mozilla, a non-profit organization that produces open source software. Firefox has numerous options for customizing your web browsing experience, including how web pages appear while surfing the Internet. By default, Firefox uses an underlined font to show clickable links within the text of a web page, to make them easily identifiable. It takes only a few seconds to turn off these underlined links by changing the saved options in your browser.
Open Firefox and click on "Tools" in the menu bar at the top of the window.
Click on "Options," then click "Content"
Click "Colors" in the "Fonts & Colors" section in the middle of the page. On the right side of the window that opens, there is a box beside "Underline links" with a check mark. Click this box to remove the check mark.
Click "OK" to save your change.
Close Firefox and restart it. Navigate to a website that has links in the text. The underlines beneath the link will now be gone.