1. SkyKakapo Browser
1.1. Features
SkyKakapo is an independent web browser developed by Tete based on the Firefox open source project.
This software is provided "as is", without warranty of any kind. The developer shall not be liable for any damages arising from its use.
It is not affiliated with the Mozilla Foundation or Mozilla Corporation. Firefox is a trademark of the Mozilla Foundation.
- SkyKakapo aims to improve performance while maintaining compatibility with Firefox, including its UI and default settings, as much as possible.
- Uses CSIR PGO. This results in optimizations that are more aligned with the actual execution patterns of the program compared to standard IR PGO (probably).
- Includes a profile import feature in the File menu.
- Includes the Menus settings page (about:preferences#menus) in Settings. You can hide unwanted items from some of the major menus.
- No installer or language packs are included.
- Patches are included in the Source folder.
1.2. Download
SkyKakapo 154.0
- x64 SSE3
-
SkyKakapo 154.0 [2026081721 en-US win64 sse3 cspgo] (91.6MB)
- MD5: 285e6a28de35f745310c3b1e4384e16f
- SHA1: a144601750f4b584b37814803dcbd3d623badee1
- SHA256: 577e6803d1fc29f121f2c684638d7aa88c76b3bbda7871f94053aefa6d8cd1ed
1.3. Migrating from Firefox Private Builds to SkyKakapo
Migration Background
I have been publishing builds based on Firefox source code with my own modifications as Firefox Private Builds since Firefox was first released.
However, according to the Mozilla Trademark Guidelines, independent projects that use Mozilla's open source code are required to use their own branding.
Therefore, I will discontinue publishing Firefox Private Builds and publish SkyKakapo, a browser with its own branding, as the successor to Firefox Private Builds.
How to Migrate Profiles
By default, Firefox Private Builds and SkyKakapo use different locations for storing profile folders. Therefore, a profile used with Firefox Private Builds cannot be used directly with SkyKakapo in the usual way.
Using SkyKakapo's profile import feature, you can copy an existing profile folder to SkyKakapo's profile folder location and register it as a SkyKakapo profile. The next section explains Firefox Private Build Profile Folder Locations.
I apologize for any inconvenience caused by the migration process, and I appreciate your understanding.
Firefox Private Build Profile Folder Locations
- Default:
-
If you are using the same profile folder as the official Firefox, individual profile folders are stored in the following folder.
%APPDATA%\Mozilla\Firefox\Profiles
- When using portable mode:
-
If Portable=1 is specified in the [General] section of the tmemutil.ini file, individual profile folders are stored in the following folder.
(PortableDataPath)\AppData\Mozilla\Firefox\Profiles
- When the profile folder path is specified using the -profile startup switch or the XRE_PROFILE_PATH environment variable:
The specified path is the profile folder path.
To easily find the profile folder of the currently running Firefox Private Build, open "Help" - "More Troubleshooting Information" and check the "Profile Folder" item under "Application Basics".
1.4. Unique Features
Profile Import Feature
You can copy an existing profile folder to SkyKakapo's profile folder location and register it as a SkyKakapo profile.
If the menu bar is not displayed, press the Alt key to show it.
Select "Import Profile..." from the File menu and specify the profile folder you want to import. The "Import Profile" dialog will open, allowing you to choose between two profile registration methods: "Classic" and "Profiles menu".

"Classic" is the classic profile registration method. It may be helpful to think of it as the same type of profile registration used in about:profiles or in the Profile Manager opened with the -p startup switch. See "Profile Manager - Create, remove or switch Firefox profiles".
-
"Profiles menu" is a relatively new profile registration method. It registers the profile in the same profile group as the current profile. Only profiles belonging to the same group as the current profile are displayed in the Profiles menu and other new profile management UIs. See "Manage Firefox profiles".

Importing may fail if the full path of a file or folder within the profile is too long. For more information, see the explanation of import failures caused by long paths.
Menus Settings Page
Includes the Menus settings page (about:preferences#menus) in Settings. You can hide unwanted items from some of the major menus.

1.5. How to Update (My Way)
- Extract the SkyKakapo 7z file to a folder of your choice using an archive utility such as 7-Zip. On Windows 11 and later, you can also extract 7z files directly in File Explorer.
- Go to the folder where the previous version of SkyKakapo is installed. If necessary, back up the following file and folder to another location:
- the tmemutil.ini file (if present)
- the folder specified by PortableDataPath (if portable mode is enabled)
- Delete the old build.
- If necessary, copy the files and folders that you backed up to another location to the new build.
- You can change the language by going to [Tools] - [Settings] - [Languages] and selecting a language under [Browser language].
1.6. Gallery
SkyKakapo Logo
Those lovely round eyes...
