With Scrapy you can crawl web sites and get their content, mainly text and images. Since it isn't possible to install Scrapy with sudo apt-get install scrapy, the recommended way is to install it inside a virtual Python environment called Anaconda.

With these commands you can get Scrapy up and running on Ubuntu 16.04:

I prefer to keep Thunderbird messages bold (unread), until I have opened them by pressing Enter, or marked them read by pressing M.

The only way I have found to get this behavior is go to Edit > Preferences > Display > Advanced, select "Automatically mark as read", select "After displaying for seconds" and enter a very high number in the seconds field.