Continuity mistake: After Antosis and the Imp Master are vanquished, in a following shot we see Phoebe wearing a robe and sitting on the bed, then we see her "Julie Bennett" reflection in the mirror, but notice that even though the style of the robe is the same, the colorful designs are quite different in the reflection. This happens again later when the sisters and Leo are seen in the mirror's reflection, as they undo the spell to reveal their true selves. (00:33:25)
Continuity mistake: When Paige and the reporters interrupt Piper and Leo's argument, Piper's arms move from out in front of her to her sides. (00:32:55)
Visible crew/equipment: When the smoke alarm starts blaring at the manor JD freaks out, and as he runs out of the door the reflection of a crew member wearing shorts is visible on the glass door. (00:23:05)
Continuity mistake: When Paige goes to talk to Henry at the police station, her arms are on her hips in the shot from the front, but down by her sides in the shot from the back. (00:14:20)
Hulkus Pocus - S8-E9
Other mistake: When Piper is explaining to Phoebe that they don't have enough time to save Billie, she lists all the things they need to do ending with "fix us and then fix Billie..." This doesn't make any sense, since when she's saying it there's nothing wrong with them to fix. It's only after she says this that they come up with the plan to infect themselves. (00:29:54)
Other mistake: When The Angel of Death comes to Leo in the car Leo asks him "can I at least see my son again?" which is an odd way to ask that question given that he has two sons.
Continuity mistake: When Paige arrives back at the manor after being stood up by Henry, Piper has both her arms on the table in front of her. Her arms are then crossed over her chest, then back on the table. (00:16:30)
Visible crew/equipment: At the bank, when Nick gets off the phone after talking to his son he walks around the stanchion, and as he says, "I never wanted to hurt anybody," we can see the light green T-mark on the floor where he had been standing. (00:29:15)
Visible crew/equipment: After orbing into the manor's attic Paige reveals to Rohtul that she switched identities with Billie, then when the real Billie walks out and joins the sisters, we can see the pink T-mark at the bottom of the screen. (00:39:35)
Repo Manor - S8-E13
Other mistake: When Piper blows up the dollhouse, killing Pilar, Phoenix and Patra, you can hear the sound effect of telekinesis, despite Piper's power being molecular combustion.
Continuity mistake: Season 8, Episode 14, "12 Angry Zen": When Phoebe finds Paige at the manor after the demon/Zodiac fight, Paige rubs her neck with her left hand. In the next shot, it's suddenly her right hand on her neck. (00:28:55)
Visible crew/equipment: When Piper is coming down the stairs with the staff, if you look in the top left corner of the stairs, you can see a piece of camera equipment moving.
The Last Temptation of Christy - S8-E15
Visible crew/equipment: At the start, Piper tells Billie she needs to be patient with Christie, and when Piper adds that if Billie needs anything they are just a call or an orb away, the pink tape mark is visible on the floor at Billie's feet. (00:01:10)
Continuity mistake: Episode 8x17, "Generation Hex": When Phoebe hands Paige her wedding gift, the way Paige holds it changes between shots. (00:01:20)
Continuity mistake: When Candor interrupts the Noxon demons torturing a student at Magic School, Rondok turns around to look at him. In the following shot, he's facing the other way and turns around again. (00:06:10)
Continuity mistake: When Phoebe and Cupid visit the memory of Phoebe revealing she is a witch to Dex, past-Phoebe has her hands down by her sides, but then her left hand suddenly jumps to her purse strap. Not only that, but in the original episode ("Rewitched"), Phoebe's hand remained on her purse strap the entire time. (00:11:05)
Gone With The Witches - S8-E20
Continuity mistake: When the leprechauns are called back to the manor from Magic School, O'Brien cradles his injured arm in his left hand. In the next shot, his arm is down by his side and he moves it to his arm again. (00:25:10)
Plot hole: When Piper goes back in time to save her sisters from dying and get rid of the Hollow, right after Leo describes it as "time catching up with itself" and the new reality Piper takes over her body. Yet in Season 5 Episode 7 "A Witch in Time", Piper goes back to keep Phoebe from saving her boyfriend but once Piper changes the past, the original Piper fades away and the new reality Piper stays.
Answer: "Hush, Hush, Hush" Paula Cole.