Re: [css-device-adapt] Need for a viewport descriptor: "zoom-behavior"

In my last mail I only described how "zoom-behavior" would work in the
viewport meta tag. Of course "zoom-behavior" could be applied as a normal
style rule as well. In this way different behaviors can be applied to
different HTML elements.

Imagine you have a blog with two columns: one contains the main content,
the other one is a sidebar. On dekstop you see both of them, on mobile the
sidebar isn't visible and only the main content can be seen. Now you could
say the whole page should be zoomed normally, except the main content which
only changes the font-size on zooming, because you don't want images to
change the size. Here is how you could do that:


body {
    zoom-behavior: "all"; // would be the default value anyway
}
main {
    zoom-behavior: "text"; // only change font-size within main while
zooming
}


Nowadays you have to choose inside the browser if the whole page or only
text should be zoomed (- at least if the browser let you choose between
these options). It isn't possible to choose only a part of a website to
change its zoom behavior. But with the "zoom-behavior" style rule it would
be possible.

Hence I don't know if "zoom-behavior" is a good wording. Maybe it should be
called "zoom-content", because it sets the content, which will be affected
by zooming.


Feedback?