QPrinter prints font DIN Regular Medium twice, slightly shifted

Hello,

I am a user of the music writing software "capella 10" (capella-software.com) which uses your PDF-Export / QPrinter functionality of the Qt-Builder.

I discovered an error regarding the font "DIN Regular Medium" (attached) which is exported/printed twice, slightly shifted to the right (see Screenshot).

You can see in the PDF (attached) that the single letters are exported twice (they can be manipulated, moved and deleted).

My questions/wishes as a user:

1. Can you reproduce this issue just with this attached font file?
2. Is this a known bug of QPrinter? Maybe it has already been discovered and fixed in a later version >5.15? (see additional information below)
3. Probably, something is wrong with the font file DIN Medium Alternate (attached). Perhaps you have an idea how I can somehow fix this font and live happily ever after?

Additional information (as far as I can say as a capella user - not a developer):

• Capella 10 currently uses the older version 5.15 (they want to keep compatibility to older systems (MacOS, iPad, Android) and are thus hesitant to migrate to the current Qt version 6.8+). As I am no developer, I cannot assess if this is already fixed in a newer version.
• However, as capella does not plan to update anytime soon, even a newer, fixed version will not help me to print my sheet music without flaws So I hope for clues to an alternate solution by fixing my font file instead
• If the capella developers set fontEmbeddingEnabled = false, then the double export does NOT happen (the filesize is bigger, it is not possible to select & modify the letters). Due to the given drawbacks, this will not be a suitable solution to this problem.

Thank you so much for your time & effort to look into this issue!