Turned out that watching Flash on FreeBSD is a non-trivial task. There is nothing to download from the Adobe site, and after installing from ports, Flash is still not visible in either Opera or Firefox. Found another workaround — will give it a try.
Open the package manager as mentioned above and look for www/linux-flashplugin7, install it. It will install nspluginwrapper too and activate the browser plugin and any other browser plugins (like adobe acroread8) too. Restart the browser and use Flash. www/linuxpluginwrapper is obsolete.