Page number formatting issue (regression since 4.6, worked in 4.5 version)

Issue type

Engraving bug (incorrect score rendering)

Description with steps to reproduce

I'm creating a new partition.

I go to Format > Style > Header and Footer (I'm using the French version; I assume that's the correct terminology).
In the right-hand side of the header, I type the code: "$P / $n" to display the page number and the total number of pages on each page.
The page numbers display correctly.

Then I go to Format > Style > Text styles and choose the "Page number" style.
For example I can add Bold effect. It works.
What doesn't work is when I try to add a Frame around the page numbers. The Frame never appears.

One solution that works for putting a border around the text is to use the "Header" Text Format and specify a border. But this is actually a bad solution because I only want to put a border around the page numbers.

Attached, I am sending you my score template in MuseScore 4.5 format, with page numbers in boxes.

PARTITION Modèle [MS] CHORALE.4-5.zip

This bad behavior appeared since version 4.6.
It worked perfectly in version 4.5.
Can you fix this software regression? Thank you.

Supporting files, videos and screenshots

PARTITION Modèle [MS] CHORALE.4-5.zip

In which versions of MuseScore Studio is this issue present?

4.6.1 and next versions

Regression

Yes, this used to work in a previous version of MuseScore 4.x

Operating system

Windows 11

Additional context

No response

Checklist

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