This is a bug fix release of VPL 3.3.3.

The fixes are:

The full regular screen mode has been update to the new standard Boost theme. The new code has been tested with the Boost, Clear, More and Essential themes.
Fixes error in background colour of similarity report
Tries to reduce terminal high load problem and blinking accuracy
Fixes a bug when resetting VPL instances
Adds check of directory and file creation. Now the plugin throws an exception if a file or directory cannot be created.
Adds php file extension to similarity checks. The plugin uses the cpp parser to checks php. This is not a full solution but is better than nothing.
The default running and debugging scripts of the required programming languages has been fixes to select properly the first source file of the submission.

Known issues

Has been found a problem with the change of the grade hide/show state. If you hide the grade in the gradebook and then unhide the grade in the VPL plugin the activity grade state is changed to shown but the state for every student grade is still hidden. As a workaround you can hide/show grade at the gradebook or at the activity setting, do not mix this setting.
Sometimes the terminal breaks the connection if receive a huge number of newlines, e.g. running a program with an infinite loop printing newlines.
There are some minor problems showing source code files using the Essential theme. These problems are about aesthetic decoration and do not reduce the functionalities.