Looks like in the latest version there still is a path possible where the consent form does not appear when the install runs.
I did find a dozen threads mentioning the toolbar with various answers but after a bit of poking I think I've tracked it down.
If you do a *fresh* install (i.e. no ImgBurn present on your system), you'll see the familiar screen asking you whether or not you want a toolbar (which you can then modify or untick).
If you do an *upgrade* however, it never appears, and as it's ticked by default, the ask installer runs unopposed, and afterward, to my surprise, firefox suddenly asked if I wanted an ask toolbar (which for me, never having seen the permission screen, briefly had intrusion alarm bells ringing).
In short: somehow the installer skips the ask toolbar permission screen when it finds an ImgBurn already present on the system, and then proceeds with default values instead of previously specified ones (i.e. it installs the toolbar). Does this at least on my WinXP x86 SP3, with ImgBurn v22.214.171.124.
Something odd is going on here. If I try to reproduce the problem more often I *do* get the ask toolbar permissions screen. As I prefer not to have toolbars and such on my system I'm quite alert during installations, so its appearance is not exactly something I'd not notice
Could it be that this only happens when upgrading from and to certain versions?