How does StartIsBack interact with Windows?

[malvinas2]

Could someone please explain me how StartIsBack works together with VisualStyles?

Well, not a detailed explanation, probably I wouldn't understand all technical details ;-)

But: Windows does not know about StartIsBack, so Windows just ignores entries ('classes') belonging to StartIsBack?
Windows 10 seems to be quite sensitive regarding visual styles, e.g. sometimes using an old visual style with a new version of Win 10 locks the whole user account. So why don't the additional classes of SiB lead to a malfunction?

(well, not a real question, I am just surprised  )

[3am]

StartIsBack supposedly uses all of the old Start Menu classes etc. once used in Windows 7 and earlier.

I think Windows 10 allows them in a visual style because they are technically still part of the msstyle though only StartIsBack is actually using them.