736264 - When dragging a selection to move it in source editor, drag image is entire text visible area

Status: NEW

(DevTools :: Source Editor, defect, P3)

Description

[Eric Shepherd [:sheppy]]

After selecting text in the Source Editor, dragging it around to move it uses a snapshot of the entire visible area of the editor instead of just the currently selected text as the drag image.

Comment 1

[Mihai Sucan [:msucan]]

Known bug. This is caused by the current drag and drop work arounds for some bugs that were in Firefox. We need to fix bug 729962 then we'll see what's the situation.

Thanks for the bug report Eric!

Comment 2

[Rob Campbell [:rc] (:robcee)]

Moving to Source Editor component.

Filter on CHELICERAE.

Comment 3

[Mihai Sucan [:msucan]]

filter on chocolate

Comment 4

[Panos Astithas (he/him) [:past] (please ni?)]

There was a seemingly-related discussion in dev-platform recently, so I'm putting a note in here and CCing ehsan in case there is more to it than removing our workarounds, as Mihai notes in comment 1:

https://groups.google.com/d/topic/mozilla.dev.platform/aHTKv_ZeP0k/discussion

Comment 5

[Mihai Sucan [:msucan]]

Thank you Panos. That's good to know!

One note: this bug is in Orion since before bug 499008 landed.

Problem explanation: we turn off/on draggable="" when the user starts dragging the text in Orion. This was the workaround for some Gecko bug that is now fixed by bug 499008. This trick confuses Firefox and it makes it believe the user drags a node, not some selected text. Hence, Firefox creates an image of the entire DOM element as the drag "icon" (or how to call it). Without any workarounds, the selected text is correctly displayed as being dragged.

Unfortunately the above only mentions the gist of the workaround - not the whole story. It is an ugly set of changes in Orion's code. It is more involved to revert the workaround. (I take the blame for the ugly code. :) )

I hope to fix this bug upstream, as soon as I clear out the Big Items for the Web Console.

Comment 6

[(no longer active)]

See the discussion in bug 781611.  If that doesn't help, you need to talk to Neil.

Comment 7

[Anton Kovalyov (:anton)]

Now that we're using CodeMirror I tried to reproduce this issue and noticed that we don't display anything anymore when dragging text around.