/usr/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/vwof@drev.com is in xul-ext-video-without-flash 3.1.1-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/../../../xul-ext/video-without-flash