How to change the order in which the windows stack on the same icon in windows taskbar

Question

In modern Windows, when an app opens multiple windows, they stack on the same icon on the task bar. The most common example would be MS Word or IE.

When you use Win+NumberKeys to quickly access taskbar apps, you can keep pressing the same number to switch between these opened windows.

I have an app that I use extremely often everyday and I put it on Win-1. But what I truly use extremely often is the secondary window it opens, which I have to press Win-1-1 to get to. I can't manually change the order of these two windows like MS Word or IE, because the secondary is secondary, and the primary can't be closed. However, occasionally (about once a week) these two windows will switch orders, so Win-1-1 becomes Win-1, which makes me really happy, but I have no idea how it happened. Does anybody know how to manually make it happen?

Answer 1

Unfortunately, the order in which buttons appear on the taskbar is entirely dependent on the order in which the windows were opened and there's no direct way to control it. It's been that way since Windows 95. Stacking just collapses windows from the same application onto a single button, but they still appear in the same order they would have without stacking. Some applications can control the behavior of their own taskbar button, but that's application specific (and the ones that do are just exploiting that behavior by reordering their own GDI window handles).

In IE and Firefox specifically (probably Chrome too - I'm not a Chrome user), the buttons on the taskbar mirror the order of your tabs, so you can reorder them by dragging your tabs into the order you want. But other than that you're out of luck unless your application has this feature.