Bug 320301 – [GTK] Cannot drag and drop (DnD) upload files to a standard HTML file upload drop zone

• Status: NEW
• Component: WebKitGTK

[Jeff Fortin]

This happens on WebKitGTK 2.52.5 + GTK 4.22.4 from Fedora 44 Workstation's RPM repositories, on GNOME 50.3's Wayland session, with both Epiphany 50.4 and MiniBrowser.


## To reproduce

1. Load https://developer.mozilla.org/en-US/docs/Web/API/HTML_Drag_and_Drop_API/File_drag_and_drop

2. Scroll (or Ctrl+F) to the "Result" heading, where there is an example widget to "Drop images here, or click to upload"

3. Drag foo.jpg from Nautilus' Downloads folder to that widget.  

4. Release the mouse/file onto that dropzone.


## Actual Results

* At step 3, there is no visual feedback that it is ready to accept the drop.
* At step 4, Epiphany replaces the whole page by loading the local image file as the view, instead of doing the drop/upload.

This is quite a problem for uploading file attachments to this Bugzilla instance here, or to GitLab.

[Jeff Fortin]

Created attachment 480802 [details]
Video demonstration

This shows the problem as it occurs on Epiphany 50.4.

[Hayden Barnes]

Filed bug 323277 with the cause and a patch: since 303828@main,
DataTransfer::allowsFileAccess() returns false on every non-Cocoa
port, so dropped files never reach dataTransfer.files. I have not
checked whether the page being replaced by the dropped file has the
same cause.