Erpnext backup with custom apps

How to backup erpnext with custom app also

Backups should be performed in the standard manner, as all data is stored in the database. Remember, when restore the backup, ensure that the bench includes any custom apps; otherwise, an error may occur.

After this I got modulenotfound Error.Not getting custom app.

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Bench have custom app.How to backup it and restore to another site

It is difficult to explain to you because you have not read the entire document. When a site is backed up, it is not taken for a particular app. No matter how many applications are installed on that site, all the data is backed up. Now when that backup is restored on a new server or a new site it should contain all the applications that were there at the time of the backup.