(1)Yes, It is 'Distro Specific'; but personally that is how I use Linux.
Packages are built specifically for a Distro, installing packages developed outside of the Distro's repository can lead to system failure down the track. Such a situation whereby you want use a later version of a program, which as yet has not been built by the Dev team of your Distro.
(2) EDIT: I use BetterPrivacy in Firefox.
Remove or manage a new and uncommon kind of cookies, better known as LSO's.The BetterPrivacy safeguard offers various ways to handle Flash-cookies set by Google, YouTube, Ebay and others...
At (1) - this I guess is a bit of a problem for products like avast and ESET. Clam AV is the only AV I have come across in the repo of any distro I've used.
At (2), I used BP until came across this:
'Obsolete Rated 5 out of 5 stars
by enieffak on July 10, 2012 · permalink
Important news on BetterPrivacy and Firefox - please read!
Since version 5 Firefox finally is capable of supporting a very basic function to remove LSO's.
This are great news, and I think we all welcome this long awaited feature. Many thanks to all users promoting and demanding a native Firefox solution for the most annoying Flash feature - for many years affecting more than 90% of all web-users globally . Though BetterPrivacy helped a lot to make people take notice of the Flash related privacy problem and hopefully also provided an acceptable temorary solution, now the main reason for promoting the BetterPrivacy add-on fortunately is obsolete. Nevertheless, I certainly know that for many of you there are good reasons to continue using BetterPrivacy. Thus I will keep on developing and supporting this add-on.
With Firefox 5 BetterPrivacy still is needed if you wish to...
know if there are LSO's stored on your hard-disk
see information about particular LSO's, e.g. their origin, name, size and date of creation/modification
remove particular LSO's only
automatically remove LSO's on Firefox startup, by a timer or even immediately.
manage or handle LSO's differently from common cookies
exclude certain LSO's or even a whole LSO folder tree from automated or manual LSO deletion
survey web-pages to detect LSO storage immediately
handle "Settings LSO's" differently from "Data/tracking LSO's", e.g. to use the native Flash manager besides BetterPrivacy
One of the most important new features introduced with this BetterPrivacy release is the option to prevent Firefox from handling LSO's the same way as common cookies. This option is activated by default, and therefore still allows to manage or delete LSO's according to the rules defined in BetterPrivacy, even if you delete cookies with a native Firefox function such as "Clear Recent History" or "Clear History When Firefox Closes".
If however you are satisfyed with just having the native Firefox option to delete LSO's when quitting Firefox and to handle LSO's like common cookies with the Firefox 'Clear Recent History'-function, you might want to uninstall the BetterPrivacy add-on or otherwise you might want to change the BetterPrivacy option "Prevent the Firefox 'Clear Recent History' functions from handling LSO's as usual cookies". Please note that disabling this option will allow Firefox to delete any LSO's whenever usual cookies are removed - regardless of the LSO protection status in BetterPrivacy.
I don't bother any more.
Apologies for the slide off-topic.