1240175 - Tooltips inconsistently hide when I move mouse over an element that shows tooltip

Status: NEW

(Toolkit :: UI Widgets, defect)

Description

[arni2033]

>>>   My Info:   Win7_64, Nightly 46, 32bit, ID 20160114060719
STR:
1. Open http://example.org/ in a new tab
2. Open bookmarks Toolbar, add http://example.org/ in bookmarks Toolbar
3. Open bookmarks Sidebar, add http://example.org/ in bookmarks Sidebar
4.A) Hover mouse over the tab in tabs toolbar.
4.B) Hover mouse over the bookmark from Step 2
4.C) Hover mouse over the bookmark from Step 3
5. Move mouse within the element from Step 4

Result:       
 After Step 4:   A,B,C - Tooltip shows up
 After Step 5:   A,B - Tooltip disappears;   C - Tooltip stays visible [OK]

Expectations: 
 Either X or Y:
 X) After Step 5 tooltip should always stay visible, because that's default tooltip behavior on Win7
 Y) After Step 5 tooltip should always hide for consistency   (I don't really support this option)