Temporary token now sent to execution server. Added prompt to load newer submission after execution.

Added interface theme selection (with custom colors option). Evaluation summary now uses details/summary html instead of js.

Submissions list & VPLs index table sorting switched to front-end. Added max grade & n° of automatic evaluations.

Added automatic conversion to Base 64 of binary file upon submission, if there is a corresponding .b64 required file

Removed gutter decoration for required files modifications because of diff complexity on large files