After a year from this article, and given the success that has received it’s time to update it.
The list could also have extensions already seen last year.
uBlock Origin/uBlock replaced AdBlock Plus in my installation because established better performances and a interface very intuitive that enable to deepen what the websites are doing.
This extension is made by the Electronic Frontier Foundation, and has proven to work very well by blocking the garbage of the sites that track you. The problem is that often some sites do not work with that, in the panel provided you can enable specific domains and often happens with social login (even with Persona) or during the registration where there are several calls for tracking.
These two extensions lighten many websites that became fast during the loading and less expensive for the computer.
Addon Update Checker
This extension allows to know which extension receive updates and to read the changes comfortably from the panel. This extension is also for Thunderbird.
The last year the name was The fox, only better but now with the new panel allows a customization of the interface very advanced.
Copy Plain Text
Adds a new button in the context menu that allows you to copy text without the HTML dirt that bothers on TinyMCE or other editor (like Google Translate).
It adds to the context menu the option to change the dictionary for spellchecking through the languages available in the browser. Very useful when writing in multiple languages on the browser.
Add on GitHub a tooltip to the names, link, ticket etc with informations. Demo available on https://justineo.github.io/github-hovercard/.
When you will answer to a ticket or a pull request there will a button to take a picture that will be published, funny and useful for making engagement with developers.
GitHub tweaks for Bugzilla
For the people that collaborate in Mozilla project is important the access to all the services, this extension add to the GitHub pull request that contain tickets for bugzilla to get an autolink.
Notifier for GitHub
Keep an eye to the GitHub tickets is important then add a beautiful button in the browser.
Navigate between the files on a repo on GitHub or GitLab can be boring then add a comfortbly sidebar to see the files.
Google Search Link Fix
Have you noticed that when you click on a link in Google get a blank page by Google that redirects you to the site you wanted to visit? This extension removes this annoyance.
I don’t care about cookies
You know this very annoying warning about cookies in the websites? This extension removes the warnings and supports many Italian sites.
The Firefox context menu contains many items but are often not used. This extension allows you to edit the menu.
New Tab Tools
About:newtab is very useful but will be better to customize!
Firefox saves a lot of information in the database sqlite after so much time they need to be optimized, this extension automatically every few days doing this work.
Reddit Enhancement Suite
Because also reddit need few enhancements like the infinite scrolling.
Thumbnail Zoom Plus
Often the thumbnail refer to a largest version, with this extension it automatically add a tooltip with the big version. Very useful in social sites.
For people like me who speaks two languages needs a spellchecker that works and that recognizes the language automatically. This extension solves this problem!
Thunderbird is comfortable in managing multiple accounts, but there is the risk of sending emails with the wrong one. This extension adds a different border depending on the email in the composition window.
The area that contains the email information with the various buttons in the email view contains a lot of information poorly organized. This extension optimizes the layout and the dimensions.
Add a search field for all address book contacts and improves the management of turning contacts into tabs.
Enhanced Desktop Notifications
In Linux environments adds support to system notifications when you receive new email, needless to say the comfortable.
We are used to having social networks with a photo of the person with which you speak because do not add also in Thunderbird?
Inverse SOGo Connector
It adds CardDAV support of Thunderbird, so I have my OwnCloud contacts synchronized on my mail client.
OwnCloud for Filelink
Thunderbird in case of large attachments can automatically upload the files on specific services then why not use your ownCloud?
It adds in the bottom bar information about the space occupied by the email in terms of MB. In this way I can control how much garbage there is around.