This is an amazing bug trail! A lot has been done and @Timo, thanks for the work so far.
I have an update that might help.
I have 2 laptops, a ASUS and a Lenovo. They both had the issue.
I did a reinstall of Ubuntu 16.04 on the Lenovo keeping the home folder. First I had the "no launcher problem" again but after update and reboot it suddenly worked. The the ASUS laptop got the same issue. I have now 2 laptops one working and one not, with the same software but apparently different settings. I saw the status being set to "Fix released" and assumed that just update+upgrade would bring in the fix.
The not working laptop (ASUS) was switched from the NVIDIA driver to the X.org X server just before the trouble started.
There is an odd way of bypassing this bug:
Go to the background image and right click and select: "Change Desktop image"
You don't want to do this but select: "All Settings".
Select: "User accounts". Create a new user. In my case the guest user. (standard, non admin)
At least in my case I can use the newly created user WITHOUT ANY PROBLEMS.
The newly created user can see and use the launcher. In this way I can at least use the computer.
At least it is a temporary fix.
The I started looking for differences between my normal user and the new guest user.
It is possible to ctrl-alt to a different tty and log in as a different user.
Some config must different and make sense but hard to compare and I do not know where to look.
So far I only found that the .Xauthority file of both is different. The have the MIT-MAGIC-COOKIE setting with different settings. Removing the .Xauthority file will have the file recreated but does not help in fixing the problem.
Please let me know how I can compare both users and where to look.
This is an amazing bug trail! A lot has been done and @Timo, thanks for the work so far.
I have an update that might help.
I have 2 laptops, a ASUS and a Lenovo. They both had the issue.
I did a reinstall of Ubuntu 16.04 on the Lenovo keeping the home folder. First I had the "no launcher problem" again but after update and reboot it suddenly worked. The the ASUS laptop got the same issue. I have now 2 laptops one working and one not, with the same software but apparently different settings. I saw the status being set to "Fix released" and assumed that just update+upgrade would bring in the fix.
My versions are on both computers:
$uname -a
4.4.0-116-generic
$apt policy libgl1-mesa-dri 0ubuntu0~ 16.04.1 0ubuntu0~ 16.04.1
libgl1-mesa-dri:
Installed: 17.2.8-
Candidate: 17.2.8-
$apt policy xserver-xorg-core
xserver-xorg-core:
Installed: 2:1.18.4-0ubuntu0.7
Candidate: 2:1.18.4-0ubuntu0.7
The not working laptop (ASUS) was switched from the NVIDIA driver to the X.org X server just before the trouble started.
There is an odd way of bypassing this bug:
Go to the background image and right click and select: "Change Desktop image"
You don't want to do this but select: "All Settings".
Select: "User accounts". Create a new user. In my case the guest user. (standard, non admin)
At least in my case I can use the newly created user WITHOUT ANY PROBLEMS.
The newly created user can see and use the launcher. In this way I can at least use the computer.
At least it is a temporary fix.
The I started looking for differences between my normal user and the new guest user.
It is possible to ctrl-alt to a different tty and log in as a different user.
Some config must different and make sense but hard to compare and I do not know where to look.
So far I only found that the .Xauthority file of both is different. The have the MIT-MAGIC-COOKIE setting with different settings. Removing the .Xauthority file will have the file recreated but does not help in fixing the problem.
Please let me know how I can compare both users and where to look.