Follow up from full page editing spike T328591.
Dependent on work done in T331935.

This task is to update our talk pages to allow for full page editing.

Design notes

1. Design: Add a place somewhere in our talk pages where a user can entire the full page editor flow.
2. Design: Should any UI/copy/logic change in the existing editor when using for full talk pages? This includes any changes needed on initial modals (onboarding, edit notices, blocked messages), the standard flow screens (wikitext editor > preview > save screens), error messages when attempting to publish, and what the success message should look like on the talk page after successfully publishing.
   • Note: We will be unable to determine what actually changed here, so we cannot automatically scroll to their update after publishing.

Engineering notes

Link to native wikitext editor proposal - https://docs.google.com/document/d/1WWwXCZPVWpnE7fg3KgUZMG2DxrKkh7NWFRvDV2O_oF8/edit

Note: Analytics will be handled in a separate task (T331937).

Designs

Link to Figma here (make sure to choose the 'Full page editing' from 'Pages' in the top left corner of Figma)

Comments:

• Full page editing will be accessed either by tapping the overflow menu and choosing the 'Edit source' option.
  • The workflow for talk page will differ a little bit from the full page article editing workflow T331935.
• The contributors land on the the wiki editor view after choosing the 'Edit' action.
• When the contributor tries to go back to the talk page screen from the editor view without publishing -> an action sheet will be displayed (similar to the one displayed when writing a comment/topic in talk pages) asking if the want to discard edit or keep editing.
• After completing an edit, the contributors can tap on 'Next' on the full page editing view, which brings them to the 'Save changes' page. From there the contributors can preview the changes by tapping on 'Show web preview'. In addition, I am proposing to add a toast when the contributor lands on the 'Preview' page for the first time.
  • Copy of toast: 'All content is shown in simplified format.' (the wording may change)
• When a contributor successfully publishes their edit a toast will appear that confirms that the edit has been published.

Talk page	Open overflow menu	Full page editing mode	Discard edit?	Publish? Preview?	Preview with toast	Successfully published the edit

Error messages
The errors are similarly displayed as the ones found in T312314. Examples below.

• Only the copy of 'Unable to publish comment due to no internet connection' changes a little bit.
  • Copy:
    • Title: Unable to publish your edit. 

    • Text: Please check your internet connection.
    • Button: Go to Settings

Unable to publish comment due to no internet connection	Server error	No internet connection