SeaMonkey 2.53.22
Released October 31, 2025
- Release Notes - The release notes describe new changes, system requirements, installation instructions, and known issues in this release - please read them carefully before using this version of SeaMonkey!
- If you are using NoScript you might encounter a certificate error when
trying to download SeaMonkey from this site. NoScript tries to force an https
connection for an http only site. It is not a NoScript problem but how the
Mozilla server, from which downloads are delivered, is configured.
In this case please add download.cdn.mozilla.net to the NoScript "Never force secure (HTTPS) connections" options or turn off NoScript for this download only. The settings are located in the NoScript options under "Advanced->HTTPS". - This release includes official Linux and Windows builds for only
x64 versions.
The Windows version is supported on Windows 7 x64 and higher only. It will not install on an unsupported version. Running the unzipped package on an unsupported version will result in an error displayed.
If you used a previous SeaMonkey x86 Windows version please uninstall it before installing the x64 version. Your profile data will be preserved doing this. - This Windows release is not signed. We are working on acquiring a new signing key but also need to integrate a new signing process into our infra. If you are concerned about the integrity of the downloads please check the binaries against the checksum files we provide.
Official builds
MD5 sums and SHA1 sums are available for official packages and source tarballs.
| Language | Version | Windows x64 |
macOS x64 |
Linux x64 |
|
|---|---|---|---|---|---|
| Chinese (Simplified) | 中文 (简体) | 2.53.22 | Download | Download | Download |
| Chinese (Traditional) | 正體中文 (繁體) | 2.53.22 | Download | Download | Download |
| Czech | Čeština | 2.53.22 | Download | Download | Download |
| Dutch | Nederlands | 2.53.22 | Download | Download | Download |
| English (British) | English (British) | 2.53.22 | Download | Download | Download |
| English (US) | English (US) | 2.53.22 | Download | Download | Download |
| Finnish | suomi | 2.53.22 | Download | Download | Download |
| French | Français | 2.53.22 | Download | Download | Download |
| Georgian | ქართული | 2.53.22 | Download | Download | Download |
| German | Deutsch | 2.53.22 | Download | Download | Download |
| Greek | Ελληνικά | 2.53.22 | Download | Download | Download |
| Hungarian | Magyar | 2.53.22 | Download | Download | Download |
| Italian | Italiano | 2.53.22 | Download | Download | Download |
| Japanese | 日本語 | 2.53.22 | Download | Download | Download |
| Norwegian (Bokmål) | Norsk bokmål | 2.53.22 | Download | Download | Download |
| Polish | Polski | 2.53.22 | Download | Download | Download |
| Portuguese (Brazilian) | Português (do Brasil) | 2.53.22 | Download | Download | Download |
| Portuguese (Portugal) | Português (Europeu) | 2.53.22 | Download | Download | Download |
| Russian | Русский | 2.53.22 | Download | Download | Download |
| Slovak | slovenčina | 2.53.22 | Download | Download | Download |
| Spanish (Argentina) | Español (de Argentina) | 2.53.22 | Download | Download | Download |
| Spanish (Spain) | Español (de España) | 2.53.22 | Download | Download | Download |
| Swedish | Svenska | 2.53.22 | Download | Download | Download |
| Turkish | Türkçe | 2.53.22 | Download | Download | Download |
Source code
The source code is available either as a tar package or from the comm source repository, mozilla source repository and l10n source repository on GitLab.
- Source Code Tarball (xz, 239 MB) - note that it doesn't unpack a subdirectory itself, so create a directory to unpack it in.
- Source Localisation Tarball (xz, 14 MB) - note that it doesn't unpack a subdirectory itself, so create a directory to unpack it in.
- The README file explains how to pull SeaMonkey 2.53.22 from the source repository.
Language Packs
See the activation notes for how to install those packages.
Chinese (Simplified), Chinese (Traditional), Czech, Dutch, English (British), English (US), Finnish, French, Georgian, German, Greek, Hungarian, Italian, Japanese, Norwegian (Bokmål), Polish, Portuguese (Brazilian), Portuguese (Portugal), Russian, Slovak, Spanish (Argentina), Spanish (Spain), Swedish,