Missing proxy class 'Drupal\context_active_trail\ProxyClass\ContextActiveTrail' for lazy service 'menu.active_trail'.

This solved the immediate problem as the decorator pattern (I've implemented in menu_block)
#2968049: Dependency Injection issue → . Probably needs a bit of clean up to remove the generator comments and remove the ignore but it does fix the problem so I'll RTBC

Patch worked for me.

Fixed, Thanks