Issue with Editor Ruler Pre-Set

I’m not confident that I’m going to describe this well, but I’ll give it my best shot.

I used Options > Editing > Formatting to set the ruler to 8" wide and saved the changes. All new documents proceeded to show up with an 8" wide typing area. Great!

However, when I used Documents > Convert > Text to Default Formatting it changed the width of the active document (whether new since the change or having been created before it) to 6" wide rather than 8".

So I went back to Formatting and changed the ruler to 6" wide and used Text to Default Formatting again. The document’s width became 4.5".

I decided to see if this worked in reverse. I changed the active document’s width to 6" and pressed the button Use Formatting in Current Editor. And the ruler in Formatting changed to display an 8" wide text area.

Can anyone explain why this is happening, or how to fix it?

Using Windows v2.9.9.14 Beta (1155038) 64-bit.