[v.17] Fix missing not saved warning

[gevorgmansuryan]

#399

[luke-]

@gevorgmansuryan Do we really need to implement a separate confirm message here?

Can't we trigger the existing Core Confirm dialogue somehow?

If the core dialogue does not allow this atm, a core update might also be useful here. This could potentially also occur in other modules.

[gevorgmansuryan]

@luke- Core Confirm dialogue is browser thing, we do not control text. Current text is from core module, and used in many places.

[luke-]

@gevorgmansuryan My point is that I would like to use the existing code here:
https://github.com/humhub/humhub/blob/master/static/js/humhub/humhub.client.js#L429

It currently looks to me as if the mail module is implementing its own unload check.

Can't we find a common reusable solution here?

[gevorgmansuryan]

@luke- i can change it to use client.confirmUnload but for this we will need to update the core minversion of mail module, because confirmUnload method is not exported. Proceed this way?

[luke-]

@luke- i can change it to use client.confirmUnload but for this we will need to update the core minversion of mail module, because confirmUnload method is not exported. Proceed this way?

@gevorgmansuryan Yes please. It is not urgent and therefore a core solution would be preferable.

[luke-]

@gevorgmansuryan Thanks ,please see my remarks below.