The goal of this issue is to contain all issues that need to be resolved to use Clean as default.

Current brainstorming about "Clean as default" can be found there:
https://docs.google.com/document/d/1ktkigIsJrxcqPeHWcDdRANA1072JVZZ0azg0INo6v48/edit

At the moment this issue is listing all issues related to Clean.

List of these epic issues by priority:
https://tracker.moodle.org/issues/?jql=%22Epic%20link%22%20%3D%20MDL-42964%20ORDER%20BY%20priority%20DESC

What should be done:
1- go through the list and prioritize the issues
2- withdraw the issues that are minor/trivial
3- add missing issues from brainstorming