Thank you sgunhouse!
Sorry have been a bit slow to get back to you on this. There are 4 extensions, and they are all DISABLED. (BTW, it used to work fine, WITH Ghostery) ... so I'm thinking I must have done something stoooopid, somewhere else?!
Just tested again, with several different websites. As before, they start to come up with home page, then the screen goes white. No, the verbiage in the URL bar thing, stays the same.
The things that's weird, it happened to both my iMac and my MBP, at around the same time. [both on OS 10.7.5 - Lion. They are NOT 'connected'.
Here's hoping you or someone can work-out if it's something I've done (tho' me doing same thing on 2 diff computers, v. unlikely (!), or is it something else!
Thank you all,
Fingers crossed xx