Martel – Uppercase dieresis' swapped dots

Describe the bug

Dieresis' dots overlap during the interpolation

To Reproduce

Type uppercase letter with a dieresis like ÖÜ

Expected behavior

Dieresis' dots shouldn't be overlapping during interpolationg

Screenshots

Additional context

This font is used by seznamzpravy.cz which is news outlet of seznam.cz which is a search engine that is used a lot in Czechia. I have already posted about this issue in Martel's repo, but it seems the designer is no longer manager of the repo.