This is how I installed searxng on Linux Mint if you need. The edited utils files attached, rename drop the .txt and move to utils dir

The file it gets its Linux installation name is /etc/os-release variable ID

$ echo $(source /etc/os-release; echo "$ID");
or
$ cat /etc/os-release

Installing Searng in Linux Mint

File: ./utils/searxng.sh

Line 104 - add linuxmint,
from
ubuntu-|debian-)
to
ubuntu-|debian-|linuxmint-*)

Line 851 - add linuxmint,
from
ubuntu-|debian-)
to
ubuntu-|debian-|linuxmint-*)

Line 871 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)...

Line 939 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)...

File: ./utils/lib.sh

Line 939 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)...

Line 946 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1104 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1148 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1159 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1211 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1237 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1260 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1317 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1400 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1430 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1464 - add linuxmint,
from
ubuntu-|debian-)...
to
ubuntu-|debian-|linuxmint-*)

Line 1503 - add linuxmint,
from
ubuntu|debian)...
to
ubuntu|debian|linuxmint)

Line 1539 - add linuxmint,
from
ubuntu|debian)...
to
ubuntu|debian|linuxmint)

Line 1563 - add linuxmint,
from
ubuntu|debian)...
to
ubuntu|debian|linuxmint)

Line 1689 - add linuxmint,
from
ubuntu|debian)...
to
ubuntu|debian|linuxmint)

File: utils/lib_redis.sh

Line 110 - add linuxmint,
from
ubuntu|debian)...
to
ubuntu|debian|linuxmint)

and...

sudo -H ./utils/searxng.sh install all
/searxng/utils/brand.sh: line 19: python: command not found
/searxng/utils/brand.sh: line 20: python: command not found
/searxng/utils/brand.sh: line 21: python: command not found

sudo apt install python3 -y
sudo ln -s /usr/bin/python3 /usr/bin/python

and

ls: cannot access '/searxng': Permission denied
ERROR: ./utils/searxng.sh: line 437: user 'searxng' missed read permission: /searxng

the user searxng does not have read persmissions on the directory

Fixed by deleting git and user and reclone and re-run install command.

SearXNG -- install user

useradd --shell /bin/bash --system --home-dir "/usr/local/searxng" --comment 'Privacy-respecting metasearch engine' searxng
mkdir "/usr/local/searxng"
mkdir: cannot create directory ‘/usr/local/searxng’: File exists
chown -R "searxng:searxng" "/usr/local/searxng"
groups searxng
-->|searxng : searxng

searxng.sh.txt
Uploading Linux_Mint_Install_searxng.txt…
lib.sh.txt
lib_redis.sh.txt