disabling all mode changes

[1-61803]

I use vimpager with a script (see subsequent comments there) to change between pager and full vim mode.

But accidentally pressing i, a, etc changes the mode while paging, which I want to prevent from happening.

I tried map i <Nop> and it works, but then I cannot restore the original behaviour, when switching back to full vim mode with ,v.

In other words, I want ,v to be the only shortcut to change from pager to full vim mode.

[rkitover]

I'll see if I can do something like that!