New KDE plasma 5.24 fingerprint login feature not working (fingerprint reader is working)

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1

Hi,

I recently updated to KDE Plasma 5.24.4 , which should now support fingerprint login automatically (KDE Plasma 5.24 will receive support for fingerprints, and other news to come) which is much smoother than the former unlocking via fingerprint approaches. I have a Lenovo Thinkpad X1 Gen7 running on Manjaro 5.17.1 and the fingerprint reader works in principle fine:

Bus 001 Device 003: ID 06cb:00bd Synaptics, Inc. Prometheus MIS Touch Fingerprint Reader

However somehow KDE does not allow me to use it to unlock. You can see here, that I can add fingerprints:

which I did. Also in the terminal the fprintd commands work fine:

thinkpad>fprintd-list ahampel
found 1 devices
Device at /net/reactivated/Fprint/Device/0
Using device /net/reactivated/Fprint/Device/0
Fingerprints for user ahampel on Synaptics Sensors (press):
 - #0: left-index-finger
 - #1: right-index-finger
 - #2: right-middle-finger
thinkpad>fprintd-verify
Using device /net/reactivated/Fprint/Device/0
Listing enrolled fingers:
 - #0: left-index-finger
 - #1: right-index-finger
 - #2: right-middle-finger
Verify started!
Verifying: left-index-finger
Verify result: verify-match (done)

But there is this strange sentence that you can see in the screenshot saying: “Logging into the system with your fingerprint is not yet supported” :

Screenshot_20220415_184352
Screenshot_20220415_184352700×138 17.6 KB

Any idea why? There is also no sign in the lock screen that looks similar to what I found in youtube videos.

Is there some configuration that I can check? I used my fingerprint reader once on this installation to unlock the screen etc but removed the pam entries again. Did KDE not update something properly?

I checked similar topics but most people seem to have trouble to get their fingerprint reader working, which is fine for me. Let me know if I overlooked another topic.

Any help welcome. Thanks.

2

Because you din’t modified your PAM rules. To enable fingerprint login with SDDM you need to add on the top in /etc/pam.d/sddm:

auth 			sufficient  	pam_fprintd.so

Do same thing for other apps if you wish use fingerprint for them (eg. sudo), but be careful to not lock your system :wink:

FInger print scanner is not working
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Hi Tomek,
thank you. That worked for me somewhat. But this is now still very similar to the way it worked already half a year ago. When I am in the lock screen I have to press enter twice, then I get this little message that I can place my finger on the finger print reader. But for example in this KDE promo video: https://cdn.kde.org/promo/Announcements/Plasma/5.24/Fingerprint_720p.webm there is no such message and no pressing enter. Just put the finger on the reader and it automatically unlocks. Hence, I wonder if this is still a different feature? Or is the only new thing in KDE plasma 5.24 that I can manage my fingerprints in a gui under settings?

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If I see correctly, this is lock screen, not login screen.

5

Ah sry, I was already one step further. I added this to my etc/pam.d/kde at the top

auth            sufficient      pam_unix.so try_first_pass likeauth nullok
auth            sufficient      pam_fprintd.so

which let’s me use the fingerprint to unlock. But as I said I have to press enter twice to activate. I guess at this stage I am almost satisfied with the solution. I am just confused what they actually added then in plasma 5.24 . Because, this is how the fingerprint unlock in kde always worked. Nothing new, and in the video it looks different.