Special Notes for OpenIndiana Starting with Firefox 60, Web Assembly (WASM) support got added to Firefox on OpenIndiana. Web Assembly wants to overcommit memory allocations in the gigabytes range. Illumos only supports this with MAP_NORESERVE. Even though 8GB of RAM does not get physically allocated during a single firefox process, Illumos still wants that memory to be available if needed. This means there needs to be enough free swap space to allocate with MAP_NORESERVE. It is recommended to have at least 32GB of swap when running firefox to allow for multiple processes to use Web Assembly. Starting with Firefox 123, the User Agent string had the OS changed from SunOS to Linux. See https://bugzilla.mozilla.org/show_bug.cgi?id=1861847 For those who want the previous behavior, consider installing the extension User-Agent Switcher and Manager. Click the extension's icon in the toolbar. In the line with userAgent, change Linux to SunOS, then cick Apply (container). For every new release of Firefox, check the userAgent string and make sure the version number is correct. As of Firefox 130, Theora video support has been removed due to low adoption. See https://bugzilla.mozilla.org/show_bug.cgi?id=1890370