Debian bookworm - Installation stops w/ error "missing" DKMS

[imago-maeror]

Running

./displaylink-debian.sh --install

results in

Unsatisfied dependencies. Missing component: DKMS.

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Checking dependencies

unzip is installed
linux-headers-6.6.13+bpo-amd64 is installed
dkms is installed
lsb-release is installed
linux-source is installed
x11-xserver-utils is installed
wget is installed
libdrm-dev:amd64 is installed
libelf-dev:amd64 is installed
git is installed
pciutils is installed
build-essential is installed

Platform requirements satisfied, proceeding ...

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Please read the Software License Agreement available at: 
https://www.synaptics.com/node/5591?filetype=exe
Do you accept?: [Y/n]: y

Downloading DisplayLink Ubuntu driver:

--2024-04-18 10:53:05--  https://www.synaptics.com/sites/default/files/exe_files/2023-08/DisplayLink%20USB%20Graphics%20Software%20for%20Ubuntu5.8-EXE.zip
Auflösen des Hostnamens www.synaptics.com (www.synaptics.com)… 54.245.106.105
Verbindungsaufbau zu www.synaptics.com (www.synaptics.com)|54.245.106.105|:443 … verbunden.
HTTP-Anforderung gesendet, auf Antwort wird gewartet … 200 OK
Länge: 18341463 (17M) [application/zip]
Wird in »DisplayLink_Ubuntu_5.8.zip« gespeichert.

DisplayLink_Ubuntu_5.8.zip                           100%[=====================================================================================================================>]  17,49M  1,16MB/s    in 20s     

2024-04-18 10:53:27 (888 KB/s) - »DisplayLink_Ubuntu_5.8.zip« gespeichert [18341463/18341463]

Removing prior: "5.8" directory

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Preparing for install

Archive:  DisplayLink_Ubuntu_5.8.zip
  inflating: 5.8/DisplayLink USB Graphics Software for Ubuntu 5.8.0-63.33-Release Notes.txt  
  inflating: 5.8/displaylink-driver-5.8.0-63.33.run  
Creating directory displaylink-driver-5.8.0-63.33
Verifying archive integrity...  100%   MD5 checksums are OK. All good.
Uncompressing DisplayLink Linux Driver 5.8.0-63.33  100%  
deleting old evdi archive
downloading evdi compatible with kernel > 6.1
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:--  0:00:01 --:--:--     0
100 87688    0 87688    0     0  44850      0 --:--:--  0:00:01 --:--:-- 44850
patching file 5.8/displaylink-driver-5.8/displaylink-installer.sh
patch unexpectedly ends in middle of line
Hunk #1 succeeded at 239 (offset 2 lines).

Installing driver version: 5.8

Distribution discovered: No LSB modules are available.
Debian GNU/Linux 12 (bookworm)
[ Installing dependencies ]

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

Reading package lists...
Building dependency tree...
Reading state information...
dkms is already the newest version (3.0.10-8+deb12u1).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
> apt install -y dkms
Do you want to continue? (Y/n) Y

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

Reading package lists...
Building dependency tree...
Reading state information...
dkms is already the newest version (3.0.10-8+deb12u1).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Unsatisfied dependencies. Missing component: DKMS.
This is a fatal error, cannot install DisplayLink Linux Software.

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Performing post install steps

sed: /lib/systemd/system/displaylink-driver.service kann nicht gelesen werden: Datei oder Verzeichnis nicht gefunden

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Starting Debug ...

Did you read Post Installation Guide? https://github.com/AdnanHodzic/displaylink-debian/blob/master/docs/post-install-guide.md [y/N] y

Did you read Troubleshooting most common issues? https://github.com/AdnanHodzic/displaylink-debian/blob/master/docs/common-issues.md [y/N] y

--------------- Linux system info ----------------

Distro: Debian
Release: bookworm
Kernel: 6.6.13+bpo-amd64

---------------- DisplayLink info ----------------

Driver version: 
DisplayLink service status: 
EVDI service version: /sys/devices/evdi/version not found

------------------ Graphics card -----------------

Vendor: i915
Subsystem: [Iris
VGA: Intel Corporation TigerLake-LP GT2 [Iris Xe Graphics] (rev 01)
VGA (3D): 
X11 version: 21.1.7-3+deb12u7

-------------- DisplayLink xorg.conf -------------

File: /etc/X11/xorg.conf.d/20-displaylink.conf
cat: /etc/X11/xorg.conf.d/20-displaylink.conf: Datei oder Verzeichnis nicht gefunden
Contents:
 

-------------------- Monitors --------------------

Providers: number : 1
Provider 0: id: 0x48 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 4 outputs: 6 associated providers: 0 name:modesetting

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My System is a DELL Latitude 9520 with Debian 12 (stable+backports). I tried different versions of the Kernel (6.1.20, 6.1.18, 6.6.13) and I added the debian backports repository to my sources.list