Opera plug-ins
From ArchWiki
If you can't get Opera working with Mozilla plug-ins, such as flashplayer, you probably don't have to install some another software. All you have to do is just to add mozilla plug-in directory path in Opera's configuration tool.
Current Opera package has it configured correctly, so you don't need to change anything. Plugins like flash work out-of-box if you have it installed. Some others, like mplayer-plugin, however still refuse to work.
The following are steps which are not needed anymore.
In Opera 8.51 follow these steps:
- Install mozilla plug-ins (e.g. flash plug-in)
pacman -S flashplugin
- Open Tools => Preferences in Opera
- Click on the Advanced tab and select Content
- Open Plug-in options...
- Open Change path...
- Open Add
- Select /opt/mozilla-plugins/ and press OK
- Open Add
- Select /opt/mozilla/lib/plugins/ and press OK
- Enjoy! ;-)