Released September 22, 2020
We strongly advise you to download the current release instead.
- 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 x64 and Windows x64 builds.
If on Linux make sure you download the appropriate installer from the download section. Most recent Linux distributions are provided in x64 (64-bit) versions only. If you choose the wrong version SeaMonkey will likely not start. The x86 (32-bit) version can be used in some x64 distributions only.
The Windows x64 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 might result in an error displayed or in erratic program behaviour.
If you use a previous SeaMonkey x86 Windows version please uninstall it before installing the x64 version. Your profile data will be preserved doing this.
The x86 version can run on any current Windows version starting with Windows 7.
- Automatic upgrades from prior versions
are disabled for this release. If you need to upgrade from an earlier
version, please download the full installer from the downloads section and
install SeaMonkey 2.53.4 manually over the previous
MD5 sums and SHA1 sums are available for official packages and source tarballs.
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, 281 MB) - note that it doesn't unpack a subdirectory itself, so create a directory to unpack it in.
- Source Localisation Tarball (xz, 11 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 2.53.4 from the source repository.
See the activation notes for how to install those packages.
Chinese (Simplified), Chinese (Traditional), Czech, Dutch, English (British), English (US), Finnish, French, Georgian, German, Hungarian, Italian, Japanese, Norwegian (Bokmål), Polish, Portuguese (Brazilian), Portuguese (Portugal), Russian, Slovak, Spanish (Argentina), Spanish (Spain), Swedish,