Published at LXer:

I guess this has been around for some time, however I was not aware of it. I bumped into it in a thread on UbuntuForums, and decided to give it a try. From the add-on page description, Flash-Aid is a Firefox 4 and 3.5 (and maybe 5 Beta too) add-on which was built to “Remove conflicting flash plugins from Ubuntu/Debian Linux systems, install the appropriate version according to system architecture and apply some tweaks to improve performance and fix common issues.”

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On Debian:
apt-get install flashplugin-nonfree
Which is basically a script to download the current version of Flash from Adobe.
or
apt-get install flashplayer-mozilla
Actually downloads a prebuilt binary and installs Flash to the proper place so it works in all browsers.

Nothing to tweak.
$ apt-cache policy flashplayer-mozilla
flashplayer-mozilla:
Installed: 2:10.3.181.22-0.0
Candidate: 2:10.3.181.22-0.0
Version table:
*** 2:10.3.181.22-0.0 0
500 http://www.debian-multimedia.org/ unstable/non-free i386 Packages
100 /var/lib/dpkg/status


Wonders yet again why a distro like Ubuntu which is supposed to be user friendly makes things so complicated.