Released on 22nd May 2021.

Changes

Rewrote Terrain Tag Editor to work with overly large tilesets.
The old sprite/icon renamer no longer runs as part of the Compiler. It is now a Debug feature. It now supports 4+ digit ID numbers, and also renames trainer charsets to the new naming conventions (which includes editing map data and metadata accordingly).
The player's charset now refreshes when a save file is loaded, and after renaming trainer charsets.
Compiler methods can now accept a file path as a parameter.
The Ball property of Pokémon in trainers.txt can now be a Poké Ball item's ID (support for numbers here will be removed in future).
Renamed trainers.txt property Ability to AbilityIndex, and added the property Ability which accepts an ability ID (and an index number for temporary backwards compatibility).

Plugins are now listed in the console when loaded, so you know what you're using.
Shortened the default inspect message for everything, and added some custom inspect methods to some classes.
Added method GameData#keys.
Made more use of nil_or_empty?.

Bug fixes

Fixed crash after an evolution happens.
Fixed being able to give the player a foreign Pokémon with a blank name.
Fixed move-learning saying the Pokémon already knows four moves if Pokemon::MAX_MOVES was changed.
Fixed changing a Pokémon's form with an item not updating the screen or doing certain other things (e.g. removing a Pokémon that was fused with another).
Fixed alternate forms not inheriting certain properties from the base form.
Fixed Rotom/Kyurem/Necrozma not learning moves upon changing form like they should.
If a Pokémon loses a move(s) because of a form change and ends up with no moves, the move learned to fill the space now shows a message saying so.
Fixed repeated known moves bug for Shadow Pokémon.
Fixed typo in egg generation.

Fixed event movement checks ignoring ledges if they're not on the top layer.
Fixed events not being able to notice the player at a distance if the event is facing left.
Fixed crash when starting a battle against two trainers who noticed you at the same time.
Made events/the player recalculate their bush depths only at the start and end of a step (and when loaded and when certain properties change), rather than every time they are queried (which is multiple times per frame).
Fixed cycling speed's charset animation not being slower as intended.
Fixed dynamic shadows not disappearing if the player is transferred elsewhere.
Fixed rounding error in positioning of overworld weather tile sprites.
Fixed bug in Sweet Scent's code relating to numbers versus symbols.

Fixed bug in starting certain trainer battles.
Fix for Pokémon not recognising they are a Mega Evolution once they become one.
Fix for inadequate code checking if a Mega Stone is unlosable by a Pokémon.
Fixed special Mega Evolution messages not being used.
Fixed typo in battle code that changes a Pokémon's type.
Fixed learning a move in battle just replacing the first known move instead of learning it properly.
Fixed invalid types for the pseudo-moves Struggle and Confusion's damage.
Fixed bug when using Metronome.
Fixed Sketch not working.
Fixed Illusion not working properly.
Fixed Poké Flute not working in battle.
Fixed bug in AI when calculating a held item's effect on damage calculation.
Fixed broken AI for Camouflage, Conversion and Conversion 2.
Fixed bug in AI that prevents switching.
Fixed crash when showing Pokédex entry after catching a new species.

Fixed not being able to force the recompiling of plugin scripts by holding Ctrl.
Fixed missing error message when a plugin is required (by another plugin) but doesn't exist.
Fixed bad encoding of plugin scripts causing accented characters to display incorrectly.

Fixed crash when trying to set a map's weather metadata via the Debug feature.
Prevented error if trying to set a species of nil for an encounter in the Encounters Editor.
Fixed trainer Pokémon's EVs and IVs not being set properly in the Encounters Editor.
Fixed bug in Encounters Editor.
Fixed Species Editor's base stats and EVs properties.
Fixed crash when saving tileset terrain tag changes in the Debug function "Edit Terrain Tags".
Fixed error when resizing an animation in the Animations Editor will delete the frame you're currently on.
Fixed changes to battle animations persisting (in the current play session only) despite not saving them in the Animation Editor.
Fixed being unable to import .anm files in the Animations Editor.
Fixed the "Give Demo Party" Debug feature not removing Pokémon already in the party before adding new ones.
Fixed the "Advanced Trainer Battle" Debug feature not working.
Fixed the "Fix Invalid Tiles" Debug feature crashing.
Disabled receiving a Mystery Gift item via the Continue/New Game's Debug menu.
Fixed the Pokémon sprite renamer not putting shiny Pokémon icons in the appropriate folder.
Fixed prevolution data not being compiled properly.
Corrected how GameData::Encounter registers its data to avoid accidental duplicates.
Fixed phone contacts being converted from old save files incorrectly.
Fixed crash when soft resetting with F12.

Fixed slightly incorrect cursor movement when choosing multiple Pokémon from the party.
Fixed inaccurate positioning of message in Hall of Fame.
Fixed holding a key in keyboard text entry not behaving as expected
Fixed phone contact details being registered incorrectly (causing a crash when calling them).
Fixed being unable to call non-trainer contacts.
Credits screen now renders text in multiple smaller bitmaps rather than one tall one.
Renamed player head icons for Town Map to the correct names.
Fixed crash when checking the length of an ogg file.
Fixed changing the Music Volume only applying to the currently playing BGM, and not applying to any later BGM played unless the Music Volume is changed again.
Fixed defs pbChooseItem, pbChooseApricorn and pbChooseFossil storing nil into a Game Variable (which gets treated as 0); they now store :NONE.
Fixed incorrect default species body shape.