[QGIS-Developer] Concerns re UX of new "duplicate features" actions in 2.99

[Nyall Dawson]

Hi all,

Just wanted to raise discussion about a concern I have with the new
"duplicate feature" / "duplicate feature and redigitize" actions which
have been added for 3.0.

While I like the functionality, I believe we should re-think the UX of
how it is exposed in the QGIS interface.

Currently, it's implemented as a "feature action", so appears in
numerous places throughout the QGIS UI, including:
- the actions drop down submenu on the toolbar
- within the right click menu for the "identify tool"
- under the "actions" heading in the identify results dock for a feature
- in a menu bar at the top of the form shown after adding a new feature
- as an entry within the right click menu in the attribute table

So my initial concern is that exposing it in all these places is
overkill and far too prominent for this operation. But my deeper
concern is that these actions skip the edit buffer and directly alter
layers in place, even when those layers are not made editable
(https://issues.qgis.org/issues/17852). So now we've got a menu item
exposed in all these places which causes permanent changes to a layer,
including in places which are not associated with editing at all (e.g.
the identify tool right click menu).

I'm also unsure what the actions would do in some contexts - e.g. if I
create a new feature and then select "duplicate feature" in the popup
form *before* this feature has even be finalized, what does it mean?

I'd very much like to see this re-thought before our final release,
and exposed in a more standard way via the advanced digitizing
toolbar.

Thoughts?

Nyall