The Instagram posts from a juror that almost derailed Gable Tostee's murder trial.

Gable Tostee was yesterday found not guilty of murdering 26-year-old Warriena Wright, but after the jury deliberated for over 13 hours, one female juror almost caused a mistrial.

Justice John Byrne said one member of the jury had mentioned the trial on her Instagram account, despite being told not to discuss the trial with anyone other than her fellow jurors.

The woman identified herself, and responded to a friend, “I’m sure you’ll have seen the trial I’m doing on the news.”

“I snagged a nasty one, so it’s a bit full on,” another post said.

“I took it home with me yesterday and woke quite miserable this morning. Will make sure I leave it behind this afternoon,” read another.

Tagging herself at the Supreme Court of Queensland, the photos in question, unearthed by ABC News, were of simple takeaway coffee cups.

Her comments, which could be seen by her followers, clearly expressed her thoughts about being part of the case.

“It’s draining,” she wrote. “It’s a high profile case…interesting to see the process though.”

One person challenged the juror, writing, “I can’t believe you posted this on Instagram during deliberations. Do you know how much court time/money will be wasted if the jury gets dismissed over this?”

Justine Byrne said the juror’s actions were “disappointing,” but did not warrant a mistrial – because the comments did not specifically mention evidence, and therefore did not interfere with Gable Tostee’s right to a fair trial.

“This is a particularly disappointing feature of the events of the day but only one is responsible for it,” Justice Byrne said.

“That juror will discover when [they] access [their] Instagram account that many members of the public have commented on [their] decision to communicate with others during the course of the trial.”

Queensland Law Society deputy president Christine Smyth told ABC, “It’s quite important — we are dealing with the lives of a young man and his family and, more importantly, a death of a young girl and her family and loved ones.”

“These are serious things to take into consideration and when we are charged with that responsibility it is important we stay well within the lines.”