The most common and most likely answer to this crossword clue is the 13 letter word CYBERBULLYING
I've seen this crossword clue in The Guardian
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Buddy explains!
The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CYBERBULLYING mean?
CYBERBULLYING verb- To bully online.
- Acts in cyberspace intended to make life unpleasant for another person.