Follow-up from #29706.
In this part, we take care of all OptionalExtension
s except for
CC: @kiwifb @dimpase @jhpalmieri @tscrim @kliem @roed314 @videlec @vbraun
Component: refactoring
Keywords: sd109
Author: Matthias Koeppe
Branch/Commit: 2821934
Reviewer: Jonathan Kliem
Issue created by migration from https://trac.sagemath.org/ticket/29720