I am not sure what you mean by 'drag & drop' in this context ...... do you mean re-arranging the order of the entries or the sections they are in or something like that?
Edit:
I have edited this from my English to standard EnglishYes, do the following:
-right-click on PC icon or Lancelot icon ( in the bottom left corner )
-A window pops up with:<configure shortcuts--Menu editor--Unlock widgets--maybe others >
-Click on <menu editor>
-A window < KDE Menu Editor > pops up.
-Change <other> to< just18>
.........>((Other is right at the bottom--You can change the name in the panel right on top at the right))
-Drag any
folder(( with content )) or a
single file from any folder to <Just18>
-On top -left.......click on save
Your menu on the desktop has changed now
Go back to desktop
Left click PC icon or Lancelot icon
Look for your name...the rest is as original ( minus what you dragged away )
Note: drag slowly.....not the speed we are used to.
If you want the original back...just go top again and click " Restore to system..."
BTW .... I see no /home/<user>/.config/menu in my install ..... will have to look further Sad ..... even though I have edited the main menu a lot.
The ....
/menu is not there original after install.
Only after you have used KmenuEdit .
EDIT:
/home/user/.local/share/applications/
is the location of my user settings for the menu Wink
OK, will nose around there and see what we can pick up !