Green Flag replaced with Play button, new Game category, support for Arduino, and 2.0 like user interface

https://block.codenori.com/

Adds support for the Marty robot

https://marty-webapp.web.app/marty-blocks

Support for DFrobot and Tello

https://school.thinkland.ai/scratch/

4 new extensions, all containing "LearningML" in their name

https://learningml.org/scratch/

Removes the sprite pane and stage and stage controls

https://scratch.twinscience.com/

Support for voice recognition and the "alert" function in JavaScript, along with a few more features.

https://scratch3.netlify.app/

Removes a lot of extensions

http://www.programmingbasics.org/en/downloads/scratchgames/scratch/

Adds a extension called "KNNClassifier"

https://scratch.dsa.im/

-Doesn't work anymore-

http://scratch.qutaojiao.com/

Adds "Completion" extension and removes some extensions.

https://stack.9dots.org/

https://aicode101.com/scratch/?lang=en-us&project=8512

Adds Robobo extension

https://scratch.theroboboproject.com/

Adds support for the PaPeRo i robot

http://paperoi-scratch3.mybluemix.net/

Adds Ohbot virtual robot support

https://scratch.ohbot.co.uk/

Adds 4 non-functional extensions

https://scratch.techpark.jp/

Adds the "whiteboard" feature, which allows you to draw and type anywhere in the Scratch GUI, and one more thing

https://scratch.leaplearner.com/

Adds support for the S-Lab Car and IoT Smart Remocon

http://sc3.socinno.com:8601/

Adds support for 2 Arduino Tools

https://labs-scratch.arduino.cc/

Adds new loading screen and 3 buttons on the navigation bar

http://yefengedu.com/scratch/scratch-gui/index.html

Removes all extensions and adds support for Tello.

http://sysdev-o.com/

Adds more turtorials in a button in Stage Control

https://scratch.fim.uni-passau.de/scratch-tutorials/

Adds a lot of new blocks as well as Addons category and a ton of extensions

https://www.adacraft.org/studio/

Adds support for simulating life

https://coderdojotrento.github.io/botch-gui/master/

Adds support for simulating physics

https://griffpatch.github.io/scratch-gui/

Adds obsolete blocks and more extensions.

https://codingclip.com/editor

Adds 2 new categories, "Featured Blocks" and "DevBlocks", and adds support for custom extensions

https://dev-blocks.powerbox1000.repl.co/

Adds support for custom extensions

https://sheeptester.github.io/scratch-gui/

Adds support for MIDI and Gamepads

https://uchiwafuujinn.github.io/scratch3webmidi/

Adds many extensions and 1 new block "move () grids", and a brand new design.

https://cocrea.world/gandi

Adds many extensions, including 8-bit sound, JS, Text to Speech but the PC's voice, and more.

https://jasonglenevans.github.io/GMSource/editor/index.html

Adds so many extensions, including Images, voice recognition, communication with Spotify, and way more!

https://scratch.machinelearningforkids.co.uk/

Adds support for so much more hardware

https://openblockcc.github.io/openblock-gui/develop/

Adds ScratchJr blocks as a extension

https://anaorodrigues.github.io/scratch-gui/

Just displays "Welcome" in Japanese. (past Scratch mod)

https://scratch3-ros.jsk.imi.i.u-tokyo.ac.jp/

Adds many new extensions, like ChatGPT2Scratch, Geo Scratch and more

https://stretch3.github.io/

Adds many new extensions, and 2 control blocks.

https://turbowarp.org/editor

Adds so many new blocks

https://d36h9x0otdrxx4.cloudfront.net/

Changes the mascot to Tera and adds 3 new extensions

https://axolotleditor.gtrees.tk/editor.html

Adds conversion from Scratch to Ruby, as well as mesh.

https://smalruby.jp/smalruby3-gui/

Adds support for so many more LEGO hardware

https://bricklife.com/scratch-gui/

Adds contrast blocks

https://ilikecereal1.github.io/scratch-gui/

Adds support for the Dexter HD robot

https://kenny2github.github.io/scratch-gui/

Adds features from ScratchTools

https://editor.scratchtools.app/

Adds a non-functional extension called Hash

https://coder-dojo-gotanda.github.io/scratch-gui/

Adds more blocks and allows importing extensions from your computer.

https://dango.shiki.online/

Adds a extension called "Database Blocks"

https://wmsi.github.io/scratch-gui/

Adds support for the WildCards hardware

https://teamwildcards.github.io/scratch-gui/

Adds a surprise button and the comment blocks from Scratch 1.2 Beta as a extension

https://tangert.github.io/scratch-gui/

Adds support for the MARK hardware

https://sansil.github.io/scratch-gui/

Adds support for the NCMB hardware

https://natsumo.github.io/scratch-gui/

Adds more blocks as a extension

https://mschae23.github.io/scratch-gui/

Adds support for the ftDuino hardware

https://harbaum.github.io/scratch-gui/

Adds a extension with a Virtual Dice

https://shrutidhariwal.github.io/scratch-gui/

Adds support for 3 ed robots

https://scratch.ed.bot/

Adds support for scientific modeling and data management

https://jaafreitas.github.io/scratch/gui/

Adds lots of new extensions

https://ide.codeskool.cc/

Adds 3 machine-related extensions

https://genirobot.co.kr/scratch3/?ckattempt=1

Removes some extensions and changes the default color to orange.

https://scratch.thecodezone.co.uk/

Adds support for downloading a image through the stage as a extension

https://scratch.digitaleducationsafety.org/

https://scratch-front.kodland.org/?lang=en

Adds support for the Poppy Robot

https://scratch.poppy-project.org/

Adds support for Tello and LEGO BOOST Remote

https://www.digikidsrobotics.net/

Adds cat blocks back

https://catblocks-archive.glitch.me/

Adds some extensions, including non-functional Speech to Text, entire body detection and more.

https://scratch.10botics.com/

Removes 2 extensions

http://scratch3.stackedu.com/

Adds more blocks and adds 2 more extensions

https://wscratch.github.io/

Adds more extensions

https://scratch.intelino.com/

Adds support for the OttoPi robot

https://www.ytani.net/scratch/

Adds new extensions

https://make.blockcode.fun/

Removed MANY blocks for just lego.

https://scratchforlego.github.io/scratch-gui/

Adds support for the Kiwrious.

https://play.ahlab.org/

Removes MANY Images

https://sammyueru.github.io/Scratchworks-gui/

Adds a new extension called VizBlocks and blankens the first costume of the default sprite.

https://visualizationliteracyplayground.github.io/scratch-gui/

(Is likely a Scratch Mod) Adds 3D and a LOT More.

https://play.creaticode.com/projects/editor