What is a CAPTCHA?
CAPTCHA Be Gone
While researching WebVisum, we discovered another problem. The extension is not "signed", another way of saying that it is considered experimental and appears not to be approved officially by Mozilla, the makers of Firefox. This matters because all add-ons that are not signed/approved, starting with Firefox 43, are disabled by default and cannot be downloaded. Firefox's help site states that one can go into Firefox and change this setting and allow unsigned add-ons to work, but it requires a high level of technical knowledge to even attempt to do this. To complicate things further, I was unable to get to the stated location and even attempt to make the change. In summary, WebVisum seems like an excellent tool; it is worth getting an invitation and waiting to see if it will again be available to use; however, it is unlikely that you will be able to use it right away. Getting WebVisum signed should be easy to do; however, it appears that its developers have chosen not to remedy the problem at this time. You may wish to contact the WebVisum team using the link on the site. The site does state that it may take a long time to get a response. The best hope, then, may be for many people to contact them, indicating to the developers that people want to use WebVisum.