DrawFocusRect function: Strange 2-pixel focus rectangle in Windows 10

Question

I noticed that the focus rectangle has changed in one of our legacy app when it works in Windows 10. It turned out that there are other old-style Microsoft apps in which we see the same effect - for example, in HTML Help Workshop. The focus rectangle must be a dotted rectangle consisting of alternating black and white dots, but we see a 2-pixel rectangle blended with the selection that looks like a red-orange rectangle:

The problem appears only on 2 computers with Windows 10, version 1909. One of them is the Pro edition, the other is the Home edition.

The focus rectangle is drawn in our app with the WinAPI DrawFocusRect function. The documentation for the DrawFocusRect function states the following:

Windows XP: The focus rectangle can now be thicker than 1 pixel, so it is more visible for high-resolution, high-density displays and accessibility needs.

But this does not help to understand why the problem occurs only on those 2 computers. They are equipped with normal 96dpi displays, and as I know, no accessibility options are turned on in them.

What it could be and how to fix the drawing of focus rectangle to see the traditional 1-pixel black/white dotted rectangle?

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If it helps, here is an example of code used to draw the focus rectangle in our VB6 app:

Dim hBrBlack As Long
hBrBlack = CreateSolidBrush(vbBlack)
FrameRect hMemDC, rcFocusRect, hBrBlack
DeleteObject hBrBlack

SetBkColor hMemDC, lColor1
SetTextColor hMemDC, lColor2
DrawFocusRect hMemDC, rcFocusRect

Answer 1

Thank you all who commented my question. The situation became clear, but not in all parts of the problem. I am resuming all what we know by now in this kind of an answer.

Yes, indeed, in Windows 10 we can open Control Panel > Ease of Access > Ease of Access Center > Make the computer easier to see and find the Make the focus rectangle thicker option:

The first thing I do not understand is that why this option became checked. Simon Mourier thinks it is a carryover from a previous Windows installation, but I doubt this is true. I definitely know that at least on my dev pc nobody checked this as only me could do that. It seems that Windows decide at some point to check this option itself depending on some system parameters.

The second incomprehensible point is why the focus rectangle became dark-orange-red. But maybe, this is by design. Perhaps, somebody in Microsoft decided that this color is the best choice for the focus rectangle.

Taking into account all this, I think, the best choice for me and other developers who need the focus rectangle in our apps is to draw the focus rectangle by ourselves using the thickness defined by the SPI_GETFOCUSBORDERHEIGHT and SPI_GETFOCUSBORDERWIDTH system parameter values.