Scripts don't work anymore with Gimp 2.10.20

[gounis]

Hello,

I've upgraded my Ubuntu to Ubuntu 20.04.1 LTS which comes with new GIMP 2.10.20. My scripts used to work fine with older version of GIMP, but I can't make them work anymore on new GIMP 2.10 no matter how much I try and look on internet.

These are the steps taken after I made a very plain script-fu just for sake of simplicity:

FIRST EXPERIMENT
-----------------------
1) These are  my script-fu folders:

~/snap/gimp/292/.config/GIMP/2.10/scripts 
/usr/share/gimp/2.0/scripts
~/.config/GIMP/2.10/scripts
~/gimp

2) I add test.scm into  [i]~/gimp [/i]folder with full 777 permissions. Content of test.scm is:

Code:

(define (script-fu-test 
(gimp-message "TEST!!!!!!!!!!")
))

3) Then, this error message appears when I refresh scripts:

Error while loading ~/gimp/test.scm: Error: unable to open "[i]~/gimp/test.scm"[/i]


SECOND EXPERIMENT
--------------------------
1) I remove ~/gimp from my script-fu folders and copy test.scm to /usr/share/gimp/2.0/scripts with the rest default GIMP scripts.
2) I go to /usr/share/gimp/2.0/scripts folder and run gimp -i -b "(test)" -b '(gimp-quit 0)' 
3) I get the following error:

gimp_check_updates_callback: loading of https://gimp.org/gimp_versions.json failed: Operation not supported

batch command experienced an execution error:
Error: eval: unbound variable: test

Since weeks, I have been trying  to make it work unsuccessfully. I don't want to go back to old GIMP so your help would be really valuable! 

Thanks in advance!