Thank you for your report. From reading the links you have posted, this seems like an intentional change and not a regression. CCing aelias@ for advice.

Right, this is working as intended and we don't plan to provide that capability again.  Window width is not under author control on desktop Chrome, therefore it shouldn't be in desktop emulation mode either.
 My comment in https://bugs.chromium.org/p/chromium/issues/detail?id=622204#c4 gives more details and an alternate way of achieving the result you want.

By the way, if you want to set width to larger than 980, just creating a div of that width should work.  For smaller than 980, you'd have to do the CSS scale I mentioned earlier.  Both should have equivalent effects to the viewport tag thing you did before.

I am well aware it was intentional on your part. However it appears, there hasn't any extended consideration around the idea that flexibility for dynamic viewport changes be left open, along the initial width locked at 980, which should be technically feasible.

It *is* a regression, in a sense that's it's been changed without dialogue with any other vendor or any consultation (to my knowledge) to a viewport spec justifying that *breaking* change. The 'Desktop Mode' features have worked the same in all mobile browsers for the past 10 years. Even opera mini allow for viewport changes. I don't think the change as implemented on Chrome, is entirely the right call.

Your argument that “window width is not under author control on Desktop” is quite irrelevant to a 'mobile viewport' environment. Width restrictions are not appropriate in the context of mobile as far I am concerned. All mobile browsers have been steering towards making dynamic viewport changes possible. This mode should not deprive authors from this capability just because one vendor suddenly feels like it. I am all open for discussion as to what you be expected of this mode with other vendors. But you introduced cross-browser incompatibilities along the way, and that alone is subject to discuss the matter more broadly.

The advice of making the width larger than 980, or using CSS, is suggesting to use ugly hacks instead of doing it properly. Those aren't viable or practical, I am afraid.

What is the harm in making 980px by default (which might very well be the right call) yet still allow a dynamic viewport change for fine tuning the user experience?

I'd like to hear a full rationale for your refusal to consider this modification just aimed at finding a middle ground resolution.