Thunderbird Version 52.9.1 for Windows Running on Windows 10 It has been called to my attention that certain hyperlinks received in Thunderbird will not open. When you hover over the hyperlink, no link is displayed in the status bar and when you click on the link, there is no response - no browser opens. Hyperlinks from other sources open normally. The only source of the problem emails so far is Groupon. I was able to duplicate by composing an email and inserting the html in the example below. Thanks for any suggestions anyone has. JIMB