There is currently a routing bug reproducible under fairly specific conditions:
Prerequisites
Category with a subcategory
Default List Filter category setting should be “no subcategories” for the parent category
Solved plugin installed
show_filter_by_solved_status site setting enabled
enable solved globally or at least for the involved categories
Repro steps
Change the solved/unsolved filter from the default of “all” to “solved”
Change the subcategory filter from the default of “none” to “all”
Observe the error in the console
Error: You didn't provide enough string/numeric parameters to satisfy all of the dynamic segments for route discovery.categoryNone. Missing params: category_slug_path_with_id
I think the cause is that Ember.js passes an incomplete transition when solved is updated, but the way we did the transition was not very elegant either. I found a workaround for the problem and fixed a bug from core too: