Resize Chrome responsive mode window without changing scale

Question

I used to be able to open developer tools, click the little icon bottom right to open responsive mode and then drag the window width handle to change the device width.

This was really useful to see how a website would perform on different devices.

However now it just changes the scale of the page, not the width - this is rubbish.

How can I change the width keeping a fixed scale?

EDIT:

Oh - may bad. It was just the website I was on. Others work fine like it used to. Oh well.

Answer 1

You need this meta tag in the head section:

<meta name="viewport" content="width=device-width,initial-scale=1">

This answer comes from here.

Answer 2

Use Toggle Device Mode by pressing the CTRL SHIFT M sequence and the page should scale if its components are responsive.