Not able to add div id names?

Hi there, i’m trying to edit the content of a page,

and I have a simple <div> tag, with some text in it.

I want to give the <div> tag an id, so am simply doing

<div id=”myId”> but each time i hit the ‘update’ button, the id is removed and it reverts back to <div>

It doesn’t matter what id name I give.

I hadn’t edited the page since March, but it was fine then with different id names for different divs. Has something changed since then?

Thanks