The jury previously heard he beat her to death with a hammer after she threatened to “reveal all” about a sexual encounter they had the previous December.
The court was told Mr Webster struck her about the head when she made the threat after saying she was pregnant and asked him to pay for an abortion.
He tied her up with duct tape and drove her back to his home, where he left the body in his workshed. Four days later, he told gardai, who were searching for her, where the body was.
Today, led through his evidence by Paul Murray BL, for the prosecution, Stephen Armstrong from Shankill, Co Dublin said he recalled getting a message from an Anne Shortall at 1.30am on a date in late March 2015.
He agreed with Mr Murray that he did not know her, never heard of her and the message was “out of the blue.”
He woke up and read the message, telling the jury it said: “Tell your mate Roy that I need €5,000 for an abortion.”
He said he replied: “Sorry, you have got the wrong number because this means nothing to me”.
She messaged back: “Sorry, hun” and he replied: “No worries, I hope it all works out for you.”
Mr Armstrong said it was about four to five minutes between the messages and he deleted them.
On April 7, he became aware that a woman was missing in Wicklow, that a body had been found and it was Anne Shortall.
He agreed with Mr Murray that this triggered his recollection of what had happened in March and he contacted the gardai.
In cross-examination, he told Brendan Grehan SC, for the defence that he had nothing to do with anyone in the case, was “contacted in error” and there was some “name confusion” with what appeared to be Mr Webster’s cousin Steven Armstrong - spelled with a V.
Steven Armstrong - Mr Webster’s second cousin - gave evidence that he only knew Ms Shortall to say hello to socially.
He knew Mr Webster well, had his number and was Facebook friends with him.
He had seen him less over the years as family commitments took over.
Two to three weeks before April 2015, he got a Facebook Messenger message at around 3am from Ms Shortall saying: “could you get Roy to get in contact with me please?” or words to that effect.
He deleted the message the minute he saw it because he “didn’t know what was going on,” he said.
Asked by Mr Murray if he had wanted to find out what was going on, he said: “no, it was nothing to do with me.”
He then rang his and the accused’s mutual cousin, Robert Webster, asking him to get in contact with the accused to ask him to ring Ms Shortall.
The following week, he received another message from Ms Shortall at the same time in the morning, this time saying: “Get Roy to get in contact with me immediately.”
Again, he deleted it and rang Roy Webster, who told him that the accused had been trying to contact Ms Shortall.
Mr Armstrong relayed this to Ms Shortall, telling her: “Answer your phone, Roy is trying to contact you.”
There was no reply and this was the last Facebook contact he had with Ms Shortall.
On March 28, he was in Fitzpatrick’s Pub when Anne Shortall came in and walked past him as he stood alone at the bar.
She went back to him and he said: “i don’t want any more contact coming to my house at that hour of the morning, or any contact at all.”
He said she looked “ashamed or shocked” and said “alright.”
In cross examination, he agreed that his wife and the accused’s were “not friends” and there was friction between them.
One of the jurors was discharged after becoming ill. The trial continues before Mr Justice Patrick McCarthy and a jury of four women and seven men.