Opening nautilus's location options menu causes excessive cpu & nautilus hang/slowdown

[Doug McMahon]

Test case:
open nautilus, click on the location options icon to expose menu (icon on far right of nautilus toolbar), close menu
What happens: nautilus cpu use gets excessive, nautilus is unresponsive for a bit.
What should happen: nothing as only exposing & closing menu

Test case 2: same as above but actually pick something from menu
What happens: again nautilus cpu use gets pegged, action takes some time to complete or completes with poor behaviour like the open terminal option

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gnome-session-flashback 1:3.18.2-1ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-10.25-generic 4.4.3
Uname: Linux 4.4.0-10-generic x86_64
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Mar 7 13:26:27 2016
InstallationDate: Installed on 2016-02-06 (29 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160205)
PackageArchitecture: all
SourcePackage: gnome-flashback
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Erick Brunzell (lbsolost)]

I can easily reproduce this behavior in a fresh install of Ubuntu GNOME Xenial:

(1) Open Nautilus
(2) Open Location options using the hamburger icon
(3) Left click on any open space - either on the desktop or on the blank background of the Nautilus window
(4) You'll now find that the Nautilus UI is totally unresponsive
(5) If you then right-click on the Nautilus tab in the top bar responsiveness returns to the UI

Additionally if you have System Monitor running on the same desktop you'll see the CPU usage nearly pegs out (see screenshot).

[Erick Brunzell (lbsolost)]

This does currently also affect the flashback session(s) but I suspect those sessions need to be using ubuntu's settings for nautilus rather than ubuntu gnome's because otherwise their is no access to nautilus > preferences. I mentioned this on their mailing list.

[dronus (paul-geisler)]

Default file manager not working.. -sigh-