976484 - Customization: Items dropped on the left side of the tab strip appear in the wrong place

Status: NEW

(Firefox :: Theme, defect)

Description

[(Currently slow to respond) Philipp Sackl [:phlsa] (Firefox UX) please use needinfo]

When dragging an item into the tab bar and releasing it on the left side of the tabs, it jumps to the right end of the tab strip.
This will become more visible when bug 963576 lands.

Comment 1

[(Currently slow to respond) Philipp Sackl [:phlsa] (Firefox UX) please use needinfo]

The desired behavior is that the item appears where it has been dropped, or at least as close to that position as possible.

Comment 2

[Matthew N. [:MattN]]

Note that this isn't just specific to the window control placeholders as it also affects the PB indicator in the tabstrip for Linux.

Perhaps we can move these non-movable items outside of the customization target so at least the outline is correct otherwise we should make it so you can drop on them to be inserted first in the target. Worst case is we use some JS to tell us set an attribute to set the target how much margin to add on the left of the target's outline.