Storage Management

MIDAS saves projects to your browser's storage. The Storage Management screen lets you view and delete saved projects, and check how much storage is in use.

Open the Storage Management Screen

In the top-right of the launcher screen header, click the rightmost of the three icons—the storage icon, which looks like a panel with horizontal lines. The Storage Management screen opens. Click the Back button in the top-left corner to return to the launcher.

View Saved Projects

The summary at the top of the screen shows the total number of saved projects and their combined size.

The table below lists each project by name and file size. Project files are Gzip-compressed when saved, and the displayed size is the actual storage consumption.

Storage Management screen showing project count and total size summary at the top, a project list table in the middle, and the Danger Zone at the bottom

Delete Projects

Deleted projects cannot be recovered. Export important projects as MDS files before deleting. To export, open the project and run File > Export Project... in the project screen.

All delete operations show a confirmation dialog. Full Application Reset requires an additional confirmation step.

Delete a Single Project

Click the X button on the project's row in the project list. A confirmation dialog appears. Click Delete to confirm.

Delete Multiple Projects

Select projects using the checkboxes. Use Select All to select all projects
Click Delete Selected
Click Delete in the confirmation dialog to remove the selected projects

Backup Folder

You can automatically back up projects to a local folder outside the browser. If you select a folder synced with a cloud storage service such as OneDrive or Dropbox, your projects become accessible from other devices.

This feature is available only in Chromium-based browsers (Chrome, Edge, etc.). It is not available in Firefox or Safari.

Configure backup

From the menu bar, select Help > Settings..., then open the Backup tab and click Choose Folder... to select a backup destination. After setup, each time you save a project, a copy of the MDS file is written to that folder. Saving the same project overwrites the previous backup.

To stop backups, click Disconnect. Files already in the folder are not deleted.

Open on another device

The first time you use a backup on another device, open the MDS file from the backup folder with Open File. The project is automatically saved to the browser.

Once a project has been saved to the browser, configuring the same backup folder lets MIDAS show a dialog when you open that project if the folder contains a file newer than the last backup made from this PC, so you can choose which version to open.

Browser support

This feature uses the File System Access API¹ and is available only in Chromium-based browsers (Chrome, Edge, etc.). In Firefox and Safari, the setting appears in Settings but is disabled. If backup is not available, export MDS files manually via File > Export Project....

Danger Zone

The Danger Zone at the bottom of the screen contains bulk data deletion operations. MIDAS stores your project data, signing keys, settings, and backup settings in browser storage. See Privacy and Security for details on storage locations.

Clear All Projects

Deletes all saved projects. Your signing keys, settings, and backup settings are not affected by this operation and are kept.

Full Application Reset

Deletes all MIDAS data: project data, signing keys, settings, and backup settings. Requires two-step confirmation.

Before running a reset, back up your signing keys using the steps in Managing Signing Keys. Signing keys are used to verify authorship and detect tampering in exported MDS files, so without a backup you will no longer be able to sign exports with your previous key.

After reset, MIDAS returns to its initial state as if opened for the first time. Signing keys and backup folder settings are also deleted by this operation. Files in the backup folder are not deleted, but the folder setting is lost, so after the reset you will need to select the folder again in the Backup tab under Help > Settings....

Comparison of Delete Operations

Operation	Projects	Signing keys	Settings	Backup settings
Clear All Projects	Deleted	Kept	Kept	Kept
Full Application Reset	Deleted	Deleted	Deleted	Deleted

Browser Storage Limitations

MIDAS data is stored in browser storage scoped to the app.midas-app.org origin.

Capacity: The browser sets a storage quota per origin. The quota varies by browser and available disk space. Check current usage in the Storage Management summary. When the quota is exceeded, saving a project fails with an error. Delete unneeded projects to free up space
Data isolation: Other sites and browser profiles cannot access your data
Data persistence: When you save a project, MIDAS requests persistent storage from the browser. If granted, the browser will not automatically evict your data even when storage is under pressure. However, clearing site data for app.midas-app.org in your browser settings deletes all MIDAS data. Clearing only cookies or cache does not affect MIDAS data