An Iraqi refugee who ran an Al Qaeda social media account from the UK has won the right to appeal against her deportation.
The woman, who was not named in court, posted more than 45,000 tweets in Arabic to more than 8,000 followers.
Her posts encouraged beheadings and urged people to travel abroad to join Al Qaeda and ISIS.
The woman, 29, served a three-and-half-year jail sentence for terrorism offences, after which the Home Office attempted to deport her.
In sentencing, Judge Charles Wide said her conduct had "affected international peace and security".
She arrived in the UK with her mother aged 15 when she was granted discretionary leave to remain.
But after her conviction, the Home Office removed those rights and refused her application for asylum.
Since Iraq had been designated a dangerous place, she was granted restricted leave to remain, but without the protection of refugee status.
The woman challenged the Home Office's decision in London's High Court where Lord Justice Warby granted her the right to appeal.
"It was suggested that she is a danger to the UK community, but the First-Tier Tribunal held that she is not," he said.
The court heard she was a "prolific poster" on Twitter and Instagram, putting up "50-60 items a day", many of which were in support of ISIS.
Despite the sentencing judge claiming her Twitter account was one of the leading Al Qaeda sites and encouraged young men to go and fight, the court heard she had suffered trauma while living in Iraq.
Mr Warby said she "had suffered from mental health difficulties, having witnessed traumatic events in Iraq which included being injured in an air strike, seeing dead bodies in the street and witnessing a raid on her grandfather's house by armed soldiers".
"She had been diagnosed with PTSD, co-morbid depression, and generalised anxiety disorder and appeared to have been socially isolated for most of her life," he said.
A hearing will be held at a later date where she will be able to appeal against the Home Office's asylum decision.
