Dropdown content on issue board -> add list is constrained by max-width

Summary

There seems to be an existing CSS rule that is applying an aggressive max-width rule that is constraining content in dropdowns:

Screenshot

Per @andr3:

[...] I believe this might be a remnant of restrictions that existed before we added milestones lists, as the dropdown should've been narrower then.

The CSS rule in question: https://gitlab.com/gitlab-org/gitlab-ee/blame/master/ee/app/assets/stylesheets/pages/boards.scss#L77

Steps to reproduce

• Visit an issue board, e.g., https://gitlab.com/groups/gitlab-org/-/boards/814296?label_name[]=Deliverable&label_name[]=Manage&label_name[]=frontend
• Click Add List
• Go to Assignees tab
• Note that lines are breaking aggressively before reaching the width of the dropdown

Example Project

https://gitlab.com/groups/gitlab-org/-/boards/814296?label_name[]=Deliverable&label_name[]=Manage&label_name[]=frontend

What is the current bug behavior?

Names and usernames are wrapping aggressively.

What is the expected correct behavior?

Names and usernames should wrap naturally when it actually exceeds the dropdown's max width.

Possible fixes

1. Remove the max-width?
2. Or extend the max-width to match new default dropdown width

• This would cause issues for custom width dropdowns though