1425515 - support FilenameConflictAction “prompt” in downloads.download()

Status: UNCONFIRMED

(WebExtensions :: Request Handling, defect, P5)

Description

[mueller_a2001]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171128222554

Steps to reproduce:

Request to download a file from an extension, using the FilenameConflictAction "prompt".


Actual results:

FilenameConflictAction "prompt" (for downloads.download()) is not supported for WebExtensions. The download fails.


Expected results:

It should be supported for WebExtensions as it was working in the old extensions. From my point of view, this was the only suitable option for downloading, as you get notified if the file already exist. I don’t want to have the file twice (why should anyone want to have the same file on disk twice? - and even if it is a different file version, the old one is most likely obsolete now). However, simply overwriting the file may also be wrong as one may accidentally overwrite a file which he wanted to keep (especially, if the files are different).