Hi Clive, Yep, having the items you mentioned to protect yourself while on the net is quite good.
I have NoScript, Ublock Origin, Blur and Ghostery installed. I've always used about:config in Firefox to set the user agent but seeing your post I went looking and found "User-Agent Switcher" which makes it much easier, so thanks for suggesting that.
Blur - Abine - has an e-mail system I use that allows me to assign an e-mail address that is unique for each web site I need one on, that way I can tell when my address has been handed off/sold because two different sites use the same e-mail address. The one I use here, 60e20f21@opayq.com, hasn't been sold off. They also can create unique credit card numbers for one time use so your cards can't be hacked. It's a good system overall.
Ghostery is rather new but seems to work well. They also have a browser for use on Android phones.
The interesting thing about the 4 ones I use is that mostly they see the same intruders but on occasion one will find one the others don't see. Blur has blocked over 12,000 trackers since March of this year. Yikes!! The free version has access to masked e-mails as well as the password & account manager.
I've often thought of setting up a computer using one of the BSD versions but never got around to it because of my need to stay the same as the places I have worked at and being a bit lazy about overcoming the learning curve.
My computer is also quite old, I think 9 years, but it might be 10.
