This ticket will entail investigating an approach as well as estimating how complex it would be to pursue the following user story:
As a Wikisource proofreader, I can retrieve my latest text via an undo button if I accidentally replace based on a new OCR transcription.
- A persistent undo button should appear only after a transcription has been replaced with a new one. It should remain for the given session/page and or be replaced until another attempt at running a transcription happens.
Note: The Undo button at the bottom of the text pane should not "disappear" after 30 seconds etc. This would make it hard for people with screenreaders or people who don't have large screens to discover this is an option.
Note: This would replace the "Are you sure you want to replace?" experience that is currently causing a pain point for users.
Related to conversation in T285415.