Discnumber No Longer Sorts in 2.89a

I use the Discnumber tag as a way to subcategorize my music. It seems that, as of 2.89a, when you sort by this field everything stays jumbled up.

I have a large library, over 23K tracks. Not sure if that matters.

Can you please check via "View > Customize Columns..." that for the Discnumber column both value and field show %discnumber% and that the "Numeric" checkbox is checked?

Yes, confirmed that %discnumber% is in both value and field boxes and "Numeric" is checked. I also noted that unchecking that seems to sort properly. I am guessing this is expected behavior?

I tried to reproduce it and in my MP3tag everything sorts fine.
Have you added anything in "sort by"?
What do you mean by "jumbled up"? that the discnumbers are in line but the track numbers are not sorted? Or that discnumber does not sort at all but everything stays as it was before?
This behaviour I could produce with a single letter in the "sort by" field.

It seems to work correctly when I uncheck the "numeric" checkbox. When "numeric" was checked and I sorted by the DiscNumber column I would see results like:


I can provide a screen shot but, as I said, the behavior seems correct with "numeric" unchecked so I am assuming it's just user error.