Has region-locked Sub-GHz transmission because of legal limitations.
Has no ability to save and send rolling codes (dynamic encrypted) in Sub-GHz, only shows them in captured list.
Factory-set device name that shows everywhere (Bluetooth broadcast, USB connection, etc) that cannot be changed.

The Flipper team has a list of device names with their corresponding production information (No shipping address) so they can assist you easier in case of an RMA.

🔓 Unleashed `DarkFlippers/unleashed-firmware`

Stable custom firmware focused on new features and improvements of original firmware components, with almost no UI changes
Very active development and Discord community.
Removes Sub-GHz regional transmission restrictions by default.
Allows Sub-GHz extended frequency range (i.e. restaurant pagers) through dangerous_settings file.
Allows changing Flipper's name via Settings->Desktop
Adds extra Sub-GHz frequencies by default without using setting_user file, setting_user is kept untouched for user settings.
Adds extra Mifare classic keys to included dict file and leaves user file untouched.
Can be used to capture, send, or make new dynamic encrypted protocols/rolling codes thats present in Official FW but locked (no encoder code was made). (Modern garage doors, etc.)
Dynamic Sub-GHz signals and codes can be added manually to pair Flipper as new remote with your system.
Current modified and new Sub-GHz protocols list can be found here.
Comes with extra apps and plugins from the general community through SD Application loader (FAP files).
- More details and full list of changes can be found in their README.

💫 RogueMaster `RogueMaster/flipperzero-firmware-wPlugins`

Built off Unleashed as the base firmware (which is a fork of Official dev firmware.)
Contains copy of Xtreme Settings App with big parts of code removed and renamed to CFW Settings
Provides closed source builds (with code taken from opensource projects) on Patreon
Removes Sub-GHz regional transmission restrictions after changes to extend_range.txt file.
Allows Sub-GHz extended frequency range (i.e. restaurant pagers) through extend_range.txt file.
Has Sub-GHz protocols and most of the other changes taken from Unleashed FW (see changes).
Adds extra custom assets (Mifare classic dict, example files, etc).
Includes some PRs from Official firmware that are not yet merged in Official firmware (Unfinished, WIP) (bleeding edge).
Includes experimental "Games Only Mode" (aka Dumb Mode).
Includes an enhanced, but experimental, new "Dolphin Level" system.
Includes extra apps and plugins from the general community through SD Application loader (FAP files).
Also includes a number of other small tweaks, changes, and a ton of additional animations.

Built from RogueMaster originally then converted to fork of Unleashed + Official FW for future development.
Adds custom UI and custom Main Menu themes, and asset packs (icons, animations)
Removes Sub-GHz regional transmission restrictions by default.
Allows Sub-GHz extended frequency range (i.e. restaurant pagers) through Xtreme Settings App.
Allows changing Flipper's name via Xtreme Settings App
Has Sub-GHz protocols and most of the other changes taken from Unleashed FW (see changes).
Adds extra custom assets (Mifare classic dict, 18+ animations (installed separately), example files, etc).
Includes an enhanced/improved "Dolphin Level" system similar to RogueMaster.
Includes extra apps and plugins from the general community through SD Application loader (FAP files).
Also includes a number of other small tweaks, changes, and stability fixes.

Fork of Unleashed FW
Adds custom-themed graphics that are not included in the Official Firmware.
Removes Sub-GHz regional transmission restrictions after changes to extend_range.txt file.
Allows Sub-GHz extended frequency range (i.e. restaurant pagers) through extend_range.txt file.
Has Sub-GHz protocols and most of the other changes taken from Unleashed FW (see changes).
Adds extra custom assets (Mifare classic dict, example files, etc).
Includes extra apps and plugins from the general community through SD Application loader (FAP files).

(OEM+)
SquachWare is abandonware for the time being! There are still some good files on it but the underlying firmware is very outdated!! I would love to resurrect the project in the future, but for now, we're on hiatus!
Adds custom animations/moods.
Includes built-in name changer! (No recompile required to change your devices name).
Includes extra community based apps and plugins through SD Application loader (FAP files).
Includes community based Bad USB scripts.
Includes community based Sub-GHz files.

Supports different keyboard layouts for Duckyscripts via the script keyword DUCKY_LANG.
Out of date with upstream Unleashed firmware, appears to not be maintained.
Includes some integrated community plugins & games but not updated FAP loader.

The dev branch is intended for public use, while others are either testing or archived hackathon submissions.
Out of date with upstream Official firmware, appears to not be maintained.
Cracking T5577 RFID passwords via dictionary attack.
Desktop header branding [WTX].
Has some frequently updated interesting experimental stuff in different branches.

Staying up to date with upstream (official) firmware is important.
TX restriction removal is illegal in most circumstances, use at your own risk.
MuddledBox was the first popular firmware fork, but didn't grow up.
Unleashed is more focused on core functionality, stability, and Sub-GHz protocols.
Xtreme is more focused on new visual tweaks, UI customisation, and other.
RogueMaster is based on Unleashed, but may be less stable than Unleashed in some circumstances.
SquachWare is forked from OFW, adding lots of custom stuff to play with out of the box all while retaining the securities and comfort of OFW.