Is there a way to disable plugins globally, but enable them on a per-site basis?
Is there a way in Firefox to globally disable plugins and allow only certain sites to run them (i.e., a whitelist)? I've tried working with CAPS, but it doesn't seem to be able to turn off <embed> or <object> tags, only certain aspects of JavaScript. I know about FlashBlock, but I've heard it's easy to circumvent and isn't meant for security. NoScript has this ability, and it's great for my own PC, but I'm looking for something more simple that I can use on the PCs of my friends and relatives.
Alle svar (1)
No, not in the basic Firefox build, and I haven't seen an extension with those features that is simple enough for the "average user" to use.
Flashblock only blocks Flash, Shockwave, and Authorware. Plugins like Java, Silverlight, and other aren't blocked by Flashblock. There is one manual control extension for JavaScript, Java, Flash, and Silverlight - Quick Java - https://addons.mozilla.org/en-US/firefox/addon/1237/ - but there is no "whitelist", only toolbar /statusbar buttons to toggle those plugins on/off.
As you mentioned, NoScript has features to block specific plugins from running automatically, and also has a "whitelist" so those plugins will run automatically on "trusted" websites, but getting the NoScript "whitelist" set up is a continuing job. It can be a frustrating extension to use for even "above-average users".
I use NoScript on my Windows desktop PC's as it is intended to be used - allowing JavaScript per domain / website by "allowing" or "temporarily allowing", but on my Linux netbook (900MHz processor and only 1GB of RAM) I have it set to Allow Scripts Globally, so I don't have to allow JavaScript for each domain on every website I visit. When I first got that netbook I ran for a few months without blocking anything, but after Firefox getting stalled by too many unnecessary plugin presentations I installed Flashblock. After a few weeks I realized that Flashblock wasn't blocking enough of the plugins that were causing problems, so I switched to NoScript with Allow Scripts Globally selected. IMO, Linux is much less of a target than Windows PC's are as far as exploits and Malware are concerned.