Plot hole: Will and Jack are out on the patio talking about the first time they met at a party (implying in college) and how Jack convinced Will to come out, but in S1E6 Jack talks about Will's favorite book in elementary school. I am re-watching the show now, and I am sure they have a conversation about hanging out as kids. Makes no sense. Time 1 is season 1 and time 2 is for Season 2. (00:06:33 - 00:13:10)
Suggested correction: I just re-watched the scene you referenced from Season 1. Jack is talking to Grace and is throwing out random Will trivia. He never said he knew Will in elementary school, just that he knows what Will's favorite book was when he was in elementary school. There is no plot hole with this statement.
Continuity mistake: In the opening scenes, Grace has red nail polish on. Later in the same scene, it has vanished as she shakes Mrs. McFarland's hand. (01:03:20 - 01:06:15)
Continuity mistake: After Will tells Jack that he knows that he hasn't told his mum he's gay, Jack backs into the patio doors, and the blind unrolls itself. In following shots it alternates from rolled up / down. (01:07:30)
Continuity mistake: When Jack is lying on the table, with the huge bowl on his face, the position of the boxes behind him on the table changes a few times. In one shot they're half hanging off of the table, in the next shot they're fully on the table etc. (01:08:15)
Continuity mistake: When Grace is preparing the food for the thanksgiving dinner, she unwraps the plastic wrapping from the bowl of cranberries, and scrunches it into a ball. In the next shot she holds it and it is unwrapped and not a ball anymore. (01:10:25)
Continuity mistake: During the thanksgiving dinner, Will is mixing salad. He then leaves the mixing spoons in the bowl. In the next shot they've vanished, and then reappear later on in the scene, back in the bowl. (01:14:00 - 01:15:35)
Visible crew/equipment: After Will and Jack come back from the patio area, into the thanksgiving dinner area, the grey boom mike can be seen reflected in the frosted glass panel above the living room door. (01:18:20)
Continuity mistake: When Grace storms out of Will's office, an orchid leaf falls from the pot she is carrying, onto the hallway floor. In the next shot it has vanished. (00:14:15)
Tea and a Total Lack of Sympathy - S2-E10
Other mistake: Karen asks Mrs. Freeman to put a stamp on her letter and pop it in the post, yet there is no writing on the envelope whatsoever. (00:28:20)
Tea and a Total Lack of Sympathy - S2-E10
Continuity mistake: As Karen is asking Mrs. Freeman to post her letter, Mrs. Freeman holds a black clipboard and a piece of paper behind the clipboard. As Karen leaves the room, between shots the piece of paper vanishes. (00:28:35)
Tea and a Total Lack of Sympathy - S2-E10
Continuity mistake: When Grace and Jack are showing their teapot, look in the background, A few of the people keep changing places depending on the camera shot. (00:30:25)
Tea and a Total Lack of Sympathy - S2-E10
Continuity mistake: When Karen is the bar, about to pay 'Smitty,' she takes out her purse, takes out her credit card and places her purse on the barside. In the next shot the purse has vanished and the credit card is suddenly in 'Smitty's' hands. (00:32:35)
Tea and a Total Lack of Sympathy - S2-E10
Continuity mistake: After Jack and Grace burst through the paper screens at the 'Antiques on the Road' show, the hole made in the screen changes between shots. (00:34:30)
Tea and a Total Lack of Sympathy - S2-E10
Continuity mistake: When Karen is in Will's office near the end, telling him why she signed the papers, she holds a black handbag in her right hand. When she says "what's that?" the handbag is hanging over her left arm. (00:40:45)
Continuity mistake: Grace puts the coffee pot down twice after pouring Will a cup, as he and Jack talk about Claire. (00:23:05)
Continuity mistake: As Grace leaves the apartment with her cereal, the location of the milk carton on the breakfast table changes more than once. (00:44:05)
Oh Dad, Poor Dad, He's Kept Me in the Closet and I'm So Sad - S2-E13
Continuity mistake: When Jack meets his father in the restaurant, his father says that he got a phone call from Karen Walker. When Jack says, "Wow," there is no sign of his arms being crossed, but when it cuts and Jack says, "I got the same phone call," his arms are suddenly crossed. (00:11:20)
Oh Dad, Poor Dad, He's Kept Me in the Closet and I'm So Sad - S2-E13
Continuity mistake: When Jack is talking to Karen in the office, Karen is thumbing through a magazine on her desk. In every shot change the pages the book is open on change. (01:08:00)
Acting Out - S2-E14
Continuity mistake: When Will and Grace walk down the street in the opening credits, in every shot change the people walking around and behind them on the streets change, and the cars on the street change too. (00:00:10)
Acting Out - S2-E14
Continuity mistake: Jack's scarf keeps changing position as he is riding his bike alongside Will and Grace, down the street. The scarf repeatedly alternates from behind/in front of his shoulder. (00:00:35)
