hi dglevy, if outdated versions of flash are enabled by default you will put any website (or third-party content that is embedded there, like rogue ads) in the position to infect your system. since newly discovered flash vulnerabilities quickly end up in exploit kits, this is widely happening on the web to spread cryptolockers and other malware, see https://blog.malwarebytes.org/malvertising-2/2015/04/booby-trapped-hugo-boss-advert-spreads-cryptowall-ransomware/ as a case study. so of course it's the responsible thing for mozilla to protect its users as far as that's possible.

if you insist in shooting yourself into the foot, then you should do research into how to disable "plugin blocklisting" in firefox. the preference you have named in your original post will have nothing to do with it and you should reset it to its default value.

hi philipp,

thank you for your reply. per your recommendation, i have restored the default setting for plugins.update.url. i did the research for turning off the forced updates and found it's quite simple: change 'extensions.blocklist.enabled' to false. i don't know why it was so hard to find this out, but it was.

i do strongly object to the assumption that i am shooting myself in the foot, however. that is an opinion not a fact. there are plenty of highly skilled computer professionals -- peter tippitt among them -- who argue that the whole security-industrial complex has gotten out of hand. it is my opinion that we are at much less risk than symantec and kaspersky would like us to believe--and i have over 16 years of direct experience to support that opinion. mozilla's plugin management module is overly paternalistic and intrusive and should allow advanced users to more easily make changes to suit their desires. i am certainly not alone. see, for example, this heated, extensive 139 comment debate, for example. A particularly choice quote: "The entire Firefox userbase is not a stupid, clueless mob."

I too disagree with my esteemed colleague philipp concerning his simile about "shooting yourself in the foot". More like this from the Urban Dictionary.