We upgraded OpenProject over the times through different versions. Since upgrading to 7.4.7 we're unable to change a story's version, when it contains tasks. Now we upgraded to 8.0.1, but the problem remains. Maybe the effect is similar to https://community.openproject.com/topics/9372, but we get different error messages.

Steps: Edit a story that already has tasks assigned. Or create a new story and assign tasks. Changing version in work package dialog gives the following error message: 

Error in dependent work package #[...]: Fixed version translation missing: en.activerecord.errors.models.work_package.attributes.fixed_version_id.task_version_must_be_the_same_as_story_version

Dragging the story from one backlog version to the other also fails (and shows an empty error message).

In production.log on the server, there is no error message fitting to it. The only warnings we get repeatedly are (times don't fit to problems)

WARN -- : Scoped order is ignored, it's forced to be batch order. 
WARN -- : Creating scope :order_by_name. Overwriting existing method Sprint.order_by_name. 

I added an SQL script to show how our table work_packages looks like. Database upgrade itself ran without problems by using 

RAILS_ENV="production" bundle exec rake db:migrate