The Dedicationachievement was changed to only require 31 total daily challenges instead of 31 consecutive daily challenges. (This change is not retroactive, meaning that any non-consecutive daily challenges you have done in the past will not count.)
The Epic Fetus and Ipecac synergy is unchanged. (It still gives +40 damage.)
Changed the difficulty of the Caves room with 4 Small Crazy Long Legs and 2 Mushrooms (#914) by removing 2 Small Crazy Long Legs and 2 rows of pits.
Replaced 2 blocks with poops in The Depths/Necropolis room #226. (This room can still soft-lock you on a minimum range build.)
The Mom void teleport has been changed to a void portal. The conditions for it appearing are the same as they were for the teleport (5%, 100+ tear damage or 20+ items).
Fixed the bug where The Compass proc from Liberty Cap would permanently stay after saving and quitting and continuing (until it happened to proc again).
Fixed the bug with the Incubus + Monstro's Lung + Tech X synergy where only one Tech X would shoot from the Incubus instead of many.
Fixed the bug with the Incubus + Monstro's Lung + Brimstone synergy where only one Brimstone would shoot from the Incubus instead of many.
Fixed the bug with the Incubus + Tech X + Mom's Knife synergy where the player could spam the tear button to shoot a Tech X ring every single frame.
Fixed the bug with the Spear of Destiny + Maw of the Void synergy where the Spear of Destiny would desync from Isaac after the Maw is activated.
Fixed the bug with Gimpy where it would completely stop working if the player had 23 luck or more.
Fixed the bug with Old Bandage where it wouldn't drop any hearts if the player has more than 29 luck.
Fixed the bug with the Ipecac + Toxic Shock synergy where Ipecac wouldn't increase the damage of the Toxic Shock. It is governed by the same +4 damage formula listed above.
Fixed the bug with The Ludovico Technique + Proptosis synergy where only the first tick of damage would properly account for the distance that the player was standing from the tear.
Fixed the bug with The Ludovico Technique + A Lump of Coal synergy where only the first the first tick of damage would properly account for the distance that the player was standing from the tear.
Fixed the bug with the Monstro's Lung + Marked synergy where Marked would act as a range down and prevent angled shots.
Fixed the bug where if the player has Isaac's Heart and uses a Sacrifice Room, they would not get any rewards but still take damage.
Fixed the bug where if the player has The Candle or Red Candle held over their head while they attempt to leave a crawlspace, the game would soft-lock.
Fixed the bug with the Dr. Fetus + Tech X synergy where the ring would generate black hearts for no reason.
Fixed the bug with the Incubus + Brimstone + Tech X synergy where the Incubus would shoot a laser ring instead of a blood ring.
Fixed the bug with the Spear of Destiny + Kidney Stone synergy where the spear would desync from Isaac when the Kidney Stone activated.
Fixed the bug where the state of Guppy's Hair Ball would be reset after saving, quitting, and continuing.
Fixed the bug where using Void to consume Breath of Life did not actually grant any invulnerability. Now, it functions as a 1-charge Void and a Breath of Life at the same time.
Fixed the bug with BBF in L-shaped rooms where it would phase through the wall.
Fixed the bug where if you selected Daddy Long Legs or It Lives from the bestiary and went back to the stats screen, the sprites would still be visible.
Fixed the bug where if the player had 1 familiar, used Box of Friends, touched an item pedestal with another familiar, and then entered a new room, the two familiars would erroneously be stacked on top of each other.
Fixed the bug where you could use Glass Cannon to steal Devil room items by using it to heal you for 1/2 of a soul heart.
Fixed the bug where it was possible to go into a Void portal during the "jumping into the chest" animation.
Fixed the bug where killing an angel spawned from a statue outside of an angel room would prevent an angel from an angel room from dropping a key piece.
Fixed the bug where it was possible to use We Need to Go Deeper! inside a crawlspace or Black Market (which had the potential to cause softlocks).
Fixed the bug where loading a mod would not properly overwrite the floor STB files.
Fixed the bug where the player would be soft-locked with no bombs on the Double Trouble room with 1 Rag Man and 2 Rag Mega (#3732).
Fixed the bug where the items from The Book of Sin were unseeded.
Fixed the bug where bombing an angel statue and killing the angel would result in a key piece becoming unobtainable.
Fixed the bug where the game would crash on most versions of Linux.
Fixed the bug where in certain situations, getting a machine from a Gift Plate would soft-lock the game. (Machines now spawn in the center of the room.)
Dedication achievement was changed to only require 31 total daily challenges instead of 31 consecutive daily challenges. (This change is not retroactive, meaning that any non-consecutive daily challenges you have done in the past will not count.)
Ipecac is overwritten by another item, it will now synergize in such a way that it adds +4 damage. (+4 damage in this context is as reported from the Found HUD.) This scales with the 
Magic Mushroom / 
Cricket's Head) multiplier and the 
Eve's Mascara multiplier. This does not scale with the 
Sacred Heart multiplier or character multipliers (like 
Judas' Shadow). For more details on how the damage calculation works, see the "Formula Information" sheet of Twinge's spreadsheet.
Epic Fetus and 
The Depths/
Necropolis room #226. (This room can still soft-lock you on a minimum range build.)
Mom's Box now works with trinkets consumed by 
Smelter or Gulp!.
Incubus + 
Cursed Eye synergy.
Jacob's Ladder + 
The Ludovico Technique + 
Monstro's Lung synergy where it would deal damage to the player.
The Compass proc from 
Liberty Cap would permanently stay after saving and quitting and continuing (until it happened to proc again).
Tech X synergy where only one Tech X would shoot from the Incubus instead of many.
Brimstone synergy where only one Brimstone would shoot from the Incubus instead of many.
Mom's Knife synergy where the player could spam the tear button to shoot a Tech X ring every single frame.
Spear of Destiny + 
Maw of the Void synergy where the Spear of Destiny would desync from Isaac after the Maw is activated.
Gimpy where it would completely stop working if the player had 23 luck or more.
Old Bandage where it wouldn't drop any hearts if the player has more than 29 luck.
Toxic Shock synergy where Ipecac wouldn't increase the damage of the Toxic Shock. It is governed by the same +4 damage formula listed above.
Proptosis synergy where only the first tick of damage would properly account for the distance that the player was standing from the tear.
A Lump of Coal synergy where only the first the first tick of damage would properly account for the distance that the player was standing from the tear.
Marked synergy where Marked would act as a range down and prevent angled shots.
Isaac's Heart and uses a Sacrifice Room, they would not get any rewards but still take damage.
Book of Shadows for another spacebar item would kill the shield from an Algiz rune, 
Celtic Cross, 
The Polaroid, or 
Empty Vessel.
Breath of Life did not work with the 
Broken Remote trinket.
Experimental Treatment could kill Blue Baby if he was at one soul heart remaining.
Cathedral would fail to spawn if there were lots of explosions or tears on the screen.
The Candle or 
Red Candle held over their head while they attempt to leave a crawlspace, the game would soft-lock.
Dr. Fetus + 
Kidney Stone synergy where the spear would desync from Isaac when the Kidney Stone activated.
Guppy's Hair Ball would be reset after saving, quitting, and continuing.
Void to consume 
BBF in L-shaped rooms where it would phase through the wall.
Box of Friends, touched an item pedestal with another familiar, and then entered a new room, the two familiars would erroneously be stacked on top of each other.
Glass Cannon to steal Devil room items by using it to heal you for 1/2 of a soul heart.
We Need to Go Deeper! inside a crawlspace or Black Market (which had the potential to cause softlocks).
Isaac's Tears + 
Chocolate Milk synergy where tears could be charged infinitely.
Cracked Crown synergy where it would not give you double stats.
Delirious would show up as normal Gurglings.
The Book of Sin were unseeded.
Robo-Baby 2.0 does not unlock anymore after defeating the Computer Savvy challenge.
The Binding of Isaac: Rebirth 
Achievements
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Cards and Runes
Challenges
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Co-op
Items
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Pills
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