(at around 1h 45 mins) Heimdell's cloak reappears during some dialogue after he discards it during the battle on the Rainbow Bridge.
(at around 1h 10 mins) Thor appears at the end of the drinks shelves to talk to Valkyrie but in the wide shot he is standing by the middle of the shelves.
Korg and his gang take the transport ship to Asgard, but Korg appears on the rainbow bridge before the ship arrives.
Valkyrie crash lands the Grandmaster's ship on the Rainbow bridge and yet Loki is able to take off with no problems when heading off to the vault.
(at around 33 mins) When Hogun first attacks Hela, he is thrown through the side of the stairs, but when he gets up after the battle, he is in front of them.
(at around 1h 50 mins) The M16 guns "Des" and "Troy" have NATO STANAG 30-round magazines, yet when they are fired they shoot far more than that. This is not possible unless they somehow have been turned into "magic guns".
When going to Doctor Strange's brownstone, at 177A Bleecker Street in Manhattan, Thor crosses a two-way street. Bleecker Street is one-way; all the cars should be going from left to right as Thor crosses the street.
When Thor is fighting in the arena, he summons lightning through his body. This would have shorted out the taser lodged in his neck, so that when the Grandmaster shocks him so that he would lose, nothing would have happened. Unless, of course, the laws of physics are different in the Marvel Universe.
Hela states that she needs to track down Heimdall so she can use his sword to open the Bifröst to expand her conquest. However, in Thần Sấm Thor (2011), Loki opened the Bifröst with Odin's golden staff. Thor is shown wielding Odin's golden staff in the throne room, presumably meaning it was there the whole time, and Hela was unaware of its use.
(at around 1h 13 mins) Thor opens the top hatch of the Quinjet and drops in. The scene then cuts to him entering from the side door. However, in the latter shot where Thor is entering, there is a bright light visible above Thor's head. The editing of this scene makes it inevitable that Thor dropped into that small corner of the Quinjet and then walked into the main control room.
(at around 1h 50 mins) When Skurge is firing his rifles "Des" and "Troy," no shells are coming out of the rifles' ejector ports.
Hella pierces the hull of the escape ship with a giant spike. Therefore it should not have been able to fly into space as it would no longer be able to hold pressure.
(at around 1h 50 mins) In the final scene with Skurge, the dust covers on the M16s he was dual wielding can be seen closed. These open upon the first round being fired.
The effect for creating the hulks voice ends up varying pitch intermittently like an audio-tune song. e.g. when David banner is talking to Thor just before being hit with green paint he changes his voice back to the hulk to say "a little weird" and the vocal note steps through several notes rather than a smooth real voice.
(at around 46 mins) While imprisoned on Sakaar, Thor kneels to pray (in the christian manner) for his father, but in the Norse religion, believers pray standing up.
(at around 30 mins) Thor, who is the god of thunder and appears to control lightning as well (which makes sense, since thunder is the sound that accompanies lightning), is disabled by Grand Master's electric shocker.
After Strange allows him to "drop in", Loki complains: "I've been falling for 30 minutes!". Loki would not have any conception of time while in the wormhole, thus, would not know how long he was falling. Besides, he isn't wearing a watch.