XFCE / Xubuntu - how take a screenshot of a screen area

By default the XFCE that is shipped in Xubuntu (as of Xubuntu 15.04) allows you to press the PrintScreen button and capture the whole screen and press alt + PrintScreen to capture the window in focus. Well, this is obviously not enough. People do need to be able to capture just a portion of the screen, it's an as frequent use case as capturing the whole screen (in my particular case it's even the most frequent use case).

But thanks to the developers of the default screenshot program in XFCE (whatever it is), there is a possibility to make screenshots of a selected screen region - we'll just have to quickly set-up a shortcut for it:

Menu => Settings => Keyboard => Application shortcut => Add => type the command:

xfce4-screenshooter -r

=> press the keys you want to be the shortcut for this action (for me it Shift + PrintScreen) => done.

(Or one could simply run the command xfce4-screenshooter -r by pressing alt + F2 to take a screenshot of an area, but it's obviously faster to create a shortcut).

How to launch 2 Skype instances on Linux

Here is how to launch several Skype instances on Linux (I currently run Skype 4.3 for Linux):

Alt+F2
skype --secondary

Pretty easy and really convenient =)

How to disable window animations on Gnome Shell 3.14 and higher

Launch dconf-editor

Go to the following sections of it:
org => gnome => desktop => interface => uncheck enable-animations

However on my system the windows started moving so briskly with the effects disabled that I actually had to enable them back.

Google Chrome or Chromium didn't shut down correctly on a system with Gnome Shell

On Ubuntu Gnome 14.10 and Sabayon with Gnome Shell I encountered the following situation when launching Google Chrome or Chromium after computer boot - the browsers would say:

"Google Chrome didn't shut down correctly"
"Chromium didn't shut down correctly"

and would offer to restore the previous tabs. Of course, the browsers had been shut down correctly before powering off the system.

Well, the cause of the error turned out to be simpler than I thought:

To stop getting the error uncheck "Continue running background apps when Chromim (Chrome) is closed".

In case you need to allow running background apps in the browsers, well, browse their respective bug-trackers for a relevant bug report and see if there are other solutions, workarounds, etc.

Skype notifications pause Rhythmbox playback

When I run both Skype and Rhythmbox, Rhythmbox is paused every time a Skype notification arrives (on receiving a new incoming message, new file transfer request, incoming call,  etc.). I find it quite annoying.

There are at least 2 ways to resolve the problem I've come across:

1) turn off all Skype notifications - and Rhythmbox is never paused. However it's not a good solution at all :)

2) edit the default.pa file in /etc/pulse/

sudo gedit /etc/pulse/default.pa

find line:

load-module module-role-cork

and comment it:

# load-module module-role-cork

save file.

Log out. Login. Voila.

P.S. The OS used was Sabayon, I've also noticed the solution applies to Fedora as well.

How to install Ruby on Rails on Ubuntu 14.04 from repos

Learning Ruby on Rails programming and looking for how to install it on Ubuntu? You must have come across different tutorials showing how install RoR on Ubuntu using various ways and particularly through RVM.

However things are much easier. Ruby and RoR are available as packages in the repos.

Install Ruby on Ubuntu 14.04 - actually it comes preinstalled. To check your Ruby version type in terminal:

ruby -v

On my machine it's outputs: "ruby 1.9.3p484 (2013-11-22 revision 43786) [x86_64-linux]"

Install Ruby on Rails on Ubuntu:

sudo apt-get install ruby-railties-4.0 // this will install RoR 4.0

sudo apt-get install ruby-railties-3.2 // this will install an earlier version of RoR

Skype mouse theme on Kubuntu 14.04 64 bit

After installing Skype on a 64 bit Kubuntu 14.04 system you notice Skype uses a different mouse theme, not the default one defined in KDE's system settings.

There was another post about what causes that, some things have changed, so here is an actual and short how to make Skype use the default mouse theme on Kubuntu 64 bit:

sudo apt-get install libxcursor1:i386

That's it.