I have been building websites on and off for many years using Notepad++, HTML, CSS, JavaScript, and PHP. During development and maintenance, I heavily use Firefox and Firefox Developer Edition on the computer where I build the sites (both editions are affected). I also have many notes on an offline website. Recently, the links in these offline websites no longer work in Firefox. They function as usual in Microsoft Edge and the newly installed Vivaldi 7. They also work on an old laptop with an older version of Firefox. I think the issue was introduced in one of the recent updates. Could you please look into this? Otherwise, I cannot use Firefox as an offline browser and the developers add-ons on my laptop anymore. Kind regards, Martijn de Jong I sent this message to Mozilla support in Dutch and would like to send an English translation as well. Do you have a solution for this issue?