Web of Trust 20170120 and lower has been blocked for your protection.

Why was it blocked?
Versions 20170120 and lower of the Web of Trust add-on send excessive user data to its service, which has been reportedly shared with third parties without sufficient sanitization. These versions are also affected by a vulnerability that could lead to unwanted remote code execution.
Who is affected?
All Firefox users who have these versions of the Web of Trust add-on installed.
What does this mean?

The problematic add-on or plugin will be automatically disabled and no longer usable.

When Mozilla becomes aware of add-ons, plugins, or other third-party software that seriously compromises Firefox security, stability, or performance and meets certain criteria, the software may be blocked from general use. For more information, please read this support article.