== Background
We would like to give users the ability to collapse the sidebar. We believe this will lead to a cleaner reading and editing experience while continuing to give access to important functionality.
== Acceptance criteria
[] Collapsed sidebar - sidebar will collapse when selecting the button adjacent to the logo
[] Limit content width (parser-output). Strictly no changes to target content that is larger than this content width. That will be worked on later. (No responsive CSS for content at this point)
[] Sidebar will be open by default for all users (with the possibility to close by default for logged-out users at a later time)
[] State of the sidebar is preserved for logged-in users across sessions (nice to have: globally)
[] Sidebar should be sticky, independent of the content
[] Try to minimize JavaScript used and favor CSS.
== Sidebar behavior
(Initial) logged-out - sidebar open, persistent throughout session
(Eventual) logged-out - sidebar closed, persistent throughout session
Logged-in - acts as a preference, persistent across sessions (nice to have, globally)
== Mockups/prototype
https://di-collapsible-sidebar-2.firebaseapp.com/Young_Thug
http://patchdemo.wmflabs.org/wikis/360edc1b162a277dd4f1f121023c7864/w/ (Code: [[ https://github.com/DemianX0/mediawiki-skins-Vector/commits/new-vector-header | GitHub - detailed ]] | [[ https://gerrit.wikimedia.org/r/c/mediawiki/skins/Vector/+/578994/3 | Gerrit - squash ]])
== Metrics (qualitative and quantitative)
[] Do people discover that the sidebar is collapsible?
[] Do people collapse it and leave it collapsed?
[] Is there any effects on account creation?
[] Is there any effect on donations?
== Testing/QA
- kowiki gadget