For hp-tools requires sudo, this is normal:
http://hplipopensource.com/hplip-web/install/manual/hp_setup.html

Could you check if the sane-backends package is installed (if not, install it and see if it helps. you might have to logout/login or reboot).

Ok, so hp-tools works ok. But although sane-backends package is installed, when running simple-scan it says "unable to start scan" and in Preferences only my webcam is listed (when running it with sudo, nothing is listed, but the scan works...). On the other side, when using sudo simple-scan I can scan normally. Maybe is a simple-scan bug?

It's strange because on the forum, someone reported me that simple-scanworks fine after the update of sane-backends.
Actually the new sane packages adds udev rules. I am pretty sure that this is where we have to dig.

PS: If you have a usb3 scanner you can try to set this environment variable SANE_USB_WORKAROUND=1 before launching simple-scan to see if it helps.

Reference task: T49

I had this problem too. I had to add my user to the scanner group (about one month ago).
I hope it help you.

Gonna need a migrator thing here to make sure users are all in the correct groups.

This is due to using setfacl in the udev rules which restricts scanners to users of the scanner group. I'm going to build a small migration system that'll run on boot,
and effectively perform any QoL changes we need to apply to live systems, such as migrating the users in the sudo and users groups into the scanner group.

Don't know if it's relevant, but perhaps R2843 rules (& group?) should be reviewed too.

Starting here: https://github.com/solus-project/qol-assist

@kyrios123 the group isn't really the issue, I agree with the package requiring a UNIX group to access the devices via udev.
The problem is we can't expect users to just manually move themselves into the right groups, this should be handled automatically.

ok. actually - maybe what I will say is stupid - but I was wondering if sane-backends shouldn't also use the scanner group instead of saned.
I guess the added value is very low apart from having multiple system groups related to scanning.

The daemon needs to be in its own group - that part is fine :)

In T4349#88231, @ikey wrote:

Starting here: https://github.com/solus-project/qol-assist

Man, this is really necessary, thanks for proposing it. I feel that lately the rolling speed of Solus has brought also some instability to their users.

@rodrum there are some hiccups, but as long as we adapt to them and don't ignore them, I think that's the most important part. i.e. responsibility to our users.

Any other examples you can think of as being appropriate to this?

I'm aware of your way to adapt and overcome difficulties, and that is what amazes me the most of Solus. In some way I feel really privileged to witness this period, because things are growing exponentially. I'm pretty confident that things will get better and better. Anyway, I have been thinking in other examples appropiate to this, and I have got to the conclussion that the pieces being affected by the momentum of the changes are mostly third party stuff. For example, VirtualBox tends to get messed up after big kernel updates, or some games in Steam in some point got messed up in my system. On the other hand, native packages tend to behave really well and I really appreciate that, but the other bits seem a little annoyed by changes around them.

Today I installed my HP printer using hplip and scanning works fine : no need to add user to group or to modify udev rules. I'm able to scan without root using simple-scan.
Therefore, maybe gnome-control-center doesn't "fully" install the printer.

@rodrum:

Re: virtualbox, we've mitigated this. @kyrios123 has packaged it up for the repos natively. It breaking on update isn't a shortcoming of Solus, it's a shortcoming of virtualbox that we've fixed in unstable.
As for the Steam games, this is why we have LSI, and a new release coming for that today, which gets things in order.

Well for me virtualbox was always shaky on changing kernels so i have switched to qemu. But is there a chance to go the dkms route for the vbox users ?

No, we have virtualbox in the unstable repos now thanks to @kyrios123 , dkms is a no go :)