too many script entries

What's the content of your /etc/grub.d - please show the output of `ls /etc/grub.d`

here the contents of /etc/grub.d

lls /etc/grub.d
00_header 11_debian_theme 14_linux_xen 17_os-prober_proxy 20_custom 30_uefi-firmware bin
05_debian_theme 12_os-prober_proxy 15_memtest86+_proxy 18_os-prober_proxy 20_linux_xen 40_custom proxifiedScripts
10_linux_proxy 13_linux_proxy 16_os-prober_proxy 19_custom_proxy 30_os-prober 41_custom README

There seem to be some duplicate scripts. This could be done by an update of grub 2, which replaces some files but doesn't find the old ones because they have new names.

You should manually remove the duplicates:

11_debian_theme
14_linux_xen
17_os-prober_proxy
20_custom
12_os-prober_proxy
18_os-prober_proxy
10_linux_proxy
13_linux_proxy
16_os-prober_proxy
19_custom_proxy

and also you should remove everything on /etc/grub.d/ proxifiedScripts except memtest86+

I tried to move the duplicates files in /etc/grub.d and all the files in /etc/grub.d/proxifiedScripts (except memtest86+) in another directory, but in the main window of grub customizer there was no kernel entries. So I tried to reinstall the kernel, but still no kernel entries.
So I had to restore all the files in their original directory and I found back the kernel entries.

ok, now I have only 9 entries in the main window of Grub Customizer and I have the right entries of the current kernel.
It seems to work, but I still have 4 empty entries called "script custom" and 2 entries called "script linux", one empty and the other one with the two lines of the current kernel (normal mode and single user mode).
Is it ok or we can do something more?

These are the files in /etc/grub.d
ls /etc/grub.d
00_header
05_debian_theme
10_linux
15_memtest86+_proxy
20_linux_xen
30_os-prober
30_uefi-firmware
40_custom
41_custom
proxifiedScripts
bin
README

and this is proxifiedScripts dir
ls /etc/grub.d/proxifiedScripts
memtest86+

Thx.

These are placeholders ("incoming entries" and "script code") right? Then this is ok, these aren't real entries (which means that they aren't visible when booting), but they do their job. There are four placeholders of the "custom" script because grub ships a 40_custom and a 41_custom. They have a slightly different behaviour, so it's not a duplicate. "incoming entries" is the place where it puts new kernels etc (also when not reconfiguring with Grub Customizer) and the "script code" placeholder is generated if the scripts creates some other content then menuentries. It controls the behaviour of Grub and should only be modified if there's a reason.

As this stuff is a little bit technical and the user don't want to change it in most cases, I decided to hide placeholders in 4.0 (by default, but there will be an option to show them).

Also I'm planning to detect and solve such duplicate problems like you had automatically.

Ok Daniel, Thx you so much for your help.
Now I wait am answer on the other question I wrote.
Cheers.

Thanks Daniel Richter, that solved my question.