Ms Tame gave evidence in a special hearing after Bester was found unfit to stand trial in February. He faces three counts of using a carriage service to menace, harass or cause offence over public posts made between April and August 2022 on Twitter, now X.
Prosecutor Ruth Champion told the court the findings were "not guilty, not guilty on grounds of insanity or a finding to the same effect", and the hearing was held to determine whether Bester committed the acts.
The tweets, read to the court, referenced a countdown to a "comeuppance" and included Ms Tame's childhood email address, which court heard was connected to her old Facebook account used during the time of the abuse. One post dated April 27, 2022 welcomed Elon Musk's takeover of Twitter and said "at last I shall come". Others in July and August 2022 included references to Donald Trump, Tommy Robinson and Milo Yiannopoulos, and said "nico bester is coming too" and "only 4 weeks to go".
Ms Tame said the posts coincided with the release of her memoir and caused her to feel "pretty close to rock bottom". She described fearing for her life after seeing them.
Bester was jailed in 2011 for sexually abusing Ms Tame when she was a 15-year-old student and he was her school teacher.