Linux : less cannot search case insensitive using -i

Question

Consider:

If searching using ?cm02csdate -i, it fails:

But if searching using ?CM02CSDATE, it can be found:

I searched the man page. It also said using -i to search case insensitive, as the following shows:

So why does it fail when I use ?cm02csdate -i?

Answer 1

The -i flag should be given to less. I.e. less -i <filename> or some_program | less -i.