Ellie's tape player should have broken when Joel pushed her into the water during the "birthday flashback," yet it still works perfectly fine when she listens to the tape Joel gives her afterward.
During the Yara death cut scene, Abby drops her pistol on the ground. After the cut scene ends and the player has control over her again, she still has it.
When playing as Abby in Santa Barbara, the player still has the option to craft ammo for their hunting pistol despite losing this and their other weapons on the island.
After Abby Shoots Tommy in the head, he somehow survives it. Yet he has hardly any signs of physical scarring, just one eye stuck closed. Even if the bullet just grazed him, it would have completely destroyed his face from the amount of blood shown when he got shot. Even if he got reconstructive surgery, it would have been beyond a miracle that he looked that good again.
Every time you use an upgrade station, the character flips on a lamp that's simply plugged into a power strip. The world is mostly without power, barring a few random generators. It can be seen that this power strip is connected to a battery.
While chasing Nora, she will barricade a double door in front of you. If you don't try to push the barricaded doors and immediately shoot the interior windows connected to the adjacent room, hop through there, and continue chasing her, she will briefly be seen running inconceivably fast down the hallway before she stops briefly to yell the line, "Shoot her!" to her friends.
After exiting the "WELCOME TO COMIC EXPO" building through the open window above a van, a bus can be seen with a misspelling of the word "TRANSPORTATION" on its side; it reads "FEDRA TRANSPORATION UNIT".
When Abby and Lev escape through the ambulance truck lodged inside a brick wall, a missing foliage texture can briefly be seen as Abby opens the vehicle's back doors.
In Ellie's section in the damp forest, there is a lamp post with a corpse hanging from it and a sign the reads "ONE WAY" with an arrow pointing left. Depending on the distance she is at from the sign, it will either appear, disappear, reappear, or re-disappear while the rest of the lamp post and corpse is still clearly visible.
During the final fight scene, the water should have washed off the blood on Ellie and Abby's skin.
The in-game text does not always reflect what is written on notes.
In the stadium where Abby can pet Bear, she can also kill him with a pipe bomb. Because this is a glitch, Bear will still appear in subsequent scenes as if he wasn't killed by Abby.
A flashlight picked off a years-dead body worked immediately. Batteries expire after several years.
A car is seen jacked up in a garage. Hydraulics could not maintain pressure over 20+ years.
When Abby is in the basement of the house with Lev, she punches in but 3 numbers for the radio call-sign, when there are more than 3 numbers.
Gasoline expires in a matter of months. After more than 20 years of untreated gas, the vehicles the characters commandeer wouldn't be drivable.
Even if Joel killed the doctor that was going to operate on Ellie, there should still be at least some doctors left in the world who could do that. Fedra for example is a much larger organization than the Fireflies were, so its likely they would have a doctor who could do that.