Ubuntu 18 and Dota 2 error   

Dota 2 can be installed on Ubuntu 18 or Linux Mint 18 with several mouse clicks. First you need to install steam from the Software Center and then download Dota 2. It is working without problems but sometimes could disconnect you or to hang up. In order to kill current running Dota and start new one you need to:

• Change the windows by:
  • ALT + TAB
• Open Linux Terminal by:
  • CTRL + ALT + T
• Run command

top

the output will be similar to:

 PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND        
25062 ursa      20   0 4624196 0,979g 343116 S  68,6  6,2   0:18.30 dota2           
 2805 ursa      20   0 3187340 384908  81664 R   3,4  2,3   9:13.81 cinnamon       
24892 ursa      20   0  381004 150832  95736 S   3,4  0,9   0:03.09 steam          
 2672 ursa       9 -11  863104  15676  11812 S   2,3  0,1  13:00.76 pulseaudio     
 4300 ursa      20   0 97,768g 126252  68556 S   2,3  0,8  10:25.15 rhythmbox        
24936 ursa      20   0  493088  36124  28588 S   2,3  0,2   0:00.53 gnome-terminal-
19260 ursa      20   0 1543808 118160  89336 S   1,7  0,7   0:47.02 Ghost         

• The you can kill Dota process by executing:

sudo kill <pid>
sudo kill -9 <pid>

Or in this case:

sudo kill 25062

or the more powerful

sudo kill -9 25062

to kill all process that you can with your user do(in case that above commands is not working):

killall -ursa

To detect which is the process running the Dota 2.

This problem is causing the mouse to not be active outside Dota 2. So you are not able to use anything else except your keyboard.