Gnome-Shell search providers are described by XML files in the folder /usr/share/gnome-shell/search_providers
You will notice two XML files - google.xml and wikipedia.xml
Lets create a new search provider - copy the google.xml file as a template
11.10
sudo cp /usr/share/gnome-shell/search_providers/google.xml /usr/share/gnome-shell/search_providers/duckduckgo.xml
12.04
sudo cp /usr/share/gnome-shell/open-search-providers/google.xml /usr/share/gnome-shell/open-search-providers/duckduckgo.xml
Now lets open the file and change some details to search with duckduckgo:
11.10
sudo nano /usr/share/gnome-shell/search_providers/duckduckgo.xml
12.04
sudo nano /usr/share/gnome-shell/open-search-providers/duckduckgo.xml
Change the following XML tags:
<ShortName>DuckDuckGo</ShortName>
<Description>DuckDuckGo Search</Description>
<Url type="text/html" method="GET" template="http://www.duckduckgo.com/?q={searchTerms}"/>
The only difficult part is finding out how a search engine searches - in duckduckgo I searched for something - you see in the title bar how the search provider adds its search terms
final result
In order to see the changes, you need to restart GNOME Shell by pressing Alt+F2, typing "r" and pressing enter.
Linked Questions:
- Is it possible to re-arrange the search providers on the GNOME Shell Activities Overview display?
You can change the click-action on Ubuntu Dock icons. Open Terminal and run
gsettings set org.gnome.shell.extensions.dash-to-dock click-action 'minimize'
Now if you click on an application icon with multiple open windows, it will switch between minimising and restoring all windows.
Best Answer
The 2nd button from left at bottom in the image you have attached is for "screen rotation lock" (landscape/portrait orientation).
Currently it is unlocked which means if you physically rotate your device screen by 90 degrees, your screen also should rotate accordingly (change orientation). When it is "locked", the screen won't change the orientation even if you physically rotate the display device (monitor).