Sharepoint - Export/Import microsoft flow in SharePoint Online

Export a Flow:

1. click on ellipsis "..." menu, select 'Export' then click on 'Package (.zip)'
2. provide a name and a description for your package and configure other options
3. click on the "Export" button in the bottom right corner your package should start downloading shortly after (or click "Download" button)

Import a Flow:

1. click on the import button in the top right hand corner of the screen upload the package file and wait for the screen to show up the package details

These instruction are provided from this page which contains helpful animations too. https://flow.microsoft.com/en-us/blog/import-export-bap-packages/

There was no such functionality to import/export flows or any other backup option previously.

But you can configure Data Loss Prevention (DLP) policies as shown here for prevention.

UPDATE

As per @SP Combatant's answer now you can import and export the flows:

Export a Flow:

1. click on ellipsis "..." menu, select 'Export' then click on 'Package (.zip)'
2. provide a name and a description for your package and configure other options
3. click on the "Export" button in the bottom right corner your package should start downloading shortly after (or click "Download" button)

Import a Flow:

• click on the import button in the top right hand corner of the screen upload the package file and wait for the screen to show up the package details

These instruction are provided from this page which contains helpful animations too. https://flow.microsoft.com/en-us/blog/import-export-bap-packages/