install hplip plugin mint

For manually installing the plugin download the *.run file in the same version as your HPLIP installation from https://developers.hp.com/hp-linux-imaging-and-printing/plugins and install it by executing the command
sh ./hplip-3.21.8-plugin.run
("cd" into the right directory first and replace the version number accordingly)

Thank you very much. I tried this solution but I got the following error message:

error: Unable to load Qt5 support. Is it installed? Try running with -i or --qt3 instead.

When I tried running the command with the --qt3 flag I get this error:

sh: 0: Illegal option --

When I tried running the command with the -i flag I got the first error again.
The errors persist regardless of prefixing the command with sudo.

Please provide the full and unedited output that you receive - including the command that you give.

Thank you. I'll paste in here 3 commands with their output:

FIRST COMMAND:
~/Downloads/hplip$ sh ./hplip-3.21.8-plugin.run
Verifying archive integrity... All good.
Uncompressing HPLIP 3.21.8 Plugin Self Extracting Archive..............................................................

HP Linux Imaging and Printing System (ver. 3.21.8)
Plugin Installer ver. 3.0

Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Plug-in version: 3.21.8
Installed HPLIP version: 3.21.8
Number of files to install: 64

note: Using PyQt5
error: Unable to load Qt5 support. Is it installed? Try running with -i or --qt3 instead.

SECOND COMMAND:
~/Downloads/hplip$ sh -i ./hplip-3.21.8-plugin.run
$ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ > > > > > > $ $ $ $ > > > $ $ > > > > > $ $ > > > > > > > > $ $ > > > > > > > $ $ > > > > > > > > > > > > > > > > > > > > > > > > $ $ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > $ $ > > > $ $ $ $ $ $ $ $ $ $ $ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > $ $ > > > > > > > > > > > > > > > > > $ $ > > > > > > > > > > > > > > > > > > > > > > $ $ > > > > > > > > > > > > > > > > > $ $ $ > > Verifying archive integrity... All good.
$ $ $ > > > > > > $ $ Uncompressing HPLIP 3.21.8 Plugin Self Extracting Archive$ $ > > $ $ $ > > > > > > > $ $ > > > > > > > > > > > > ..............................................................$
$ $ $ $ > > > > > > > > > > > > >
HP Linux Imaging and Printing System (ver. 3.21.8)
Plugin Installer ver. 3.0

Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Plug-in version: 3.21.8
Installed HPLIP version: 3.21.8
Number of files to install: 64

note: Using PyQt5
error: Unable to load Qt5 support. Is it installed? Try running with -i or --qt3 instead.

THIRD COMMAND:
~/Downloads/hplip$ sh --qt3 ./hplip-3.21.8-plugin.run
sh: 0: Illegal option --

the option goes after the file name:

sh ./hplip-3.21.8-plugin.run --qt3

Does it matter that I've downloaded the plugin run file to it's own directory in my downloads directory? I tried running the revised command, but I got a new error message. The two commands I tried are pasted in below along with their output:

FIRST COMMAND:
~/Downloads/hplip$ sh ./hplip-3.21.8-plugin.run --qt3
Unrecognized flag : --qt3
Makeself version 2.1.5
 1) Getting help or info about ./hplip-3.21.8-plugin.run :
  ./hplip-3.21.8-plugin.run --help Print this message
  ./hplip-3.21.8-plugin.run --info Print embedded info : title, default target directory, embedded script ...
  ./hplip-3.21.8-plugin.run --lsm Print embedded lsm entry (or no LSM)
  ./hplip-3.21.8-plugin.run --list Print the list of files in the archive
  ./hplip-3.21.8-plugin.run --check Checks integrity of the archive

 2) Running ./hplip-3.21.8-plugin.run :
  ./hplip-3.21.8-plugin.run [options] [--] [additional arguments to embedded script]
  with following options (in that order)
  --confirm Ask before running embedded script
  --noexec Do not run embedded script
  --keep Do not erase target directory after running
   the embedded script
  --nox11 Do not spawn an xterm
  --nochown Do not give the extracted files to the current user
  --target NewDirectory Extract in NewDirectory
  --tar arg1 [arg2 ...] Access the contents of the archive through the tar command
  -- Following arguments will be passed to the embedded script

SECOND COMMAND:
~/Downloads/hplip$ sh ./hplip-3.21.8-plugin.run -i
Unrecognized flag : -i
Makeself version 2.1.5
 1) Getting help or info about ./hplip-3.21.8-plugin.run :
  ./hplip-3.21.8-plugin.run --help Print this message
  ./hplip-3.21.8-plugin.run --info Print embedded info : title, default target directory, embedded script ...
  ./hplip-3.21.8-plugin.run --lsm Print embedded lsm entry (or no LSM)
  ./hplip-3.21.8-plugin.run --list Print the list of files in the archive
  ./hplip-3.21.8-plugin.run --check Checks integrity of the archive

 2) Running ./hplip-3.21.8-plugin.run :
  ./hplip-3.21.8-plugin.run [options] [--] [additional arguments to embedded script]
  with following options (in that order)
  --confirm Ask before running embedded script
  --noexec Do not run embedded script
  --keep Do not erase target directory after running
   the embedded script
  --nox11 Do not spawn an xterm
  --nochown Do not give the extracted files to the current user
  --target NewDirectory Extract in NewDirectory
  --tar arg1 [arg2 ...] Access the contents of the archive through the tar command
  -- Following arguments will be passed to the embedded script

It's not easy to correctly interpret the error message, but you need to execute

sh ./hplip-3.21.8-plugin.run -- --qt3

I tried running that exact command, but I still get an error message. Notably, it says at the end "option --qt3 not recognized." I gather that qt3 may be an older version of the software (the error message itself suggests using the --qt5 flag, although that doesn't seem to work either). The command and its output follow:

~/Downloads/hplip$ sh ./hplip-3.21.8-plugin.run -- --qt3
Verifying archive integrity... All good.
Uncompressing HPLIP 3.21.8 Plugin Self Extracting Archive..............................................................

HP Linux Imaging and Printing System (ver. 3.21.8)
Plugin Installer ver. 3.0

Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Self-installs the HPLIP plugin.

Usage: hplip-plugin-install [MODE] [OPTIONS]

[MODE]
  Run in graphical -u or --gui (Default)
  UI mode:
  Run in interactive -i or --interactive
  mode:

[OPTIONS]
  Use Qt5: --qt5 (Default)
  Set the logging -l<level> or --logging=<level>
  level:
                      <level>: none, info*, error, warn, debug (*default)
  Run in debug mode: -g (same as option: -ldebug)
  This help -h or --help
  information:

error: option --qt3 not recognized

Maybe the following version works:

sh ./hplip-3.21.8-plugin.run -- -i