In new Ubuntu OS, the default Desktop session is Wayland. there is a possibility that you will encounter the issue that the captured screen image is a black screen. 


Here are the solutions to deal with such issue. 


Solution 1:


1. Launch Worksnaps Client using command line. You can do so by opening a Terminal, then executing the following commands:


cd ~/WSClient/

./run.sh


Try to look for a message "gnome-screenshot command NOT found" in the output. If the message is there, you need to install gnome-screenshot. 


You can can install gnome-screenshot by using the following command:


sudo apt install gnome-screenshot




Then you can start Worksnaps Client again by the same command, i.e., 


./run.sh


Log in using your credentials, select project/task and start to log time. Then you can check whether screenshots can be captured normally. 


If screenshots can be captured normally, the next time you can use the desktop shortcut to start Worksnaps Client (i.e., using the usual way), the screenshots should be captured successfully from now on. 



Solution 2:


1. Create a text file <home>/timetracker/display_type.txt. (You can use vi or your favorite text editor.). You should already have a folder named "timetracker" in your home directory, you just need to create the file display_type.txt under the "timetracker" directory. 


2. Put a single line into the display_type.txt file. The single line will be "wayland" (without the quotes). Save the file display_type.txt. 


3. Start Worksnaps Client as usual. 


4. When screenshots are captured and uploaded to the server, check to see whether the screenshots are normal.