Feature Request: Warn on Unsaved Data

[billdenney]

When work has been done but not saved, it could help to have a warning if the work would be lost. The UI that I'm thinking of is:

• Flag modifications:
  • When anything is done after "load image" or "webcam capture" (or any way of loading a new image), a flag is set indicating that modifications have been made.
  • When the user does any form of export (like "Export JSON" or exporting a dataset to .csv), the flag is cleared.
• Warn when losing data
  • If the modifications flag is set and the user does something that would lose the data (load a new image, import JSON, leave the page, etc.), the user is warned that they have unsaved data, and would they like to continue?
    • If yes, data is cleared. If no, the action is cancelled.

[ankitrohatgi]

This is quite doable. Thanks for the suggestion.