Problem/Motivation
When creating a new block via block layout region is not stored.
Steps to reproduce
1) Go to /admin/structure/blocks
2) Use the 'Place Block' function next to a region, for example the 'Sidebar Second'.
3) Choose 'add custom block'
4) On the 'Configure Block'-page the region you've selected on step #2 is not selected.
Proposed resolution
Use a URL parameter to remember/set the region like we do for theme
Remaining tasks
User interface changes
When creating a new block the region will be remembered.
API changes
NA
Data model changes
NA
Release notes snippet
NA
