Рейтинг 4 из 5 звёзд

от Пользователь Firefox 682d7c Дек. 8, 2017 · permalink

for thunderbird52 and linux, remove the old extension of contact sidebar and go to add-ons manager window.
Now drag-drop contactssidebar-1.7.1.zip file to this window and appears the option to install the new extension.