Debian: CapsLock like on Windows (Macbook Air edition)

How to configure the keyboard on Debian in order for capslock to function like on Windows, using a french Apple Keyboard (French (Macintosh)).

Solution found here, adapted for my old french Macbook Air.

Configuration file to create:

cat <<EOF | sudo tee /usr/share/X11/xkb/symbols/mswindows-capslock
// $XKeyboardConfig$

// Replicate a "feature" of MS Windows on AZERTY keyboards 
// where Caps Lock also acts as a Shift Lock on number keys.
// Include keys <AE01> to <AE10> in the FOUR_LEVEL_ALPHABETIC key type.
// adapted for apple french keyboard
  
partial alphanumeric_keys
xkb_symbols "basic" {
    key <TLDE> { type= "FOUR_LEVEL_ALPHABETIC", [              at,     numbersign, periodcentered,      Ydiaeresis ] };
    key <AE01> { type= "FOUR_LEVEL_ALPHABETIC", [       ampersand,              1,     VoidSymbol,      dead_acute ] };
    key <AE02> { type= "FOUR_LEVEL_ALPHABETIC", [          eacute,              2,     ediaeresis,          Eacute ] };
    key <AE03> { type= "FOUR_LEVEL_ALPHABETIC", [        quotedbl,              3,     VoidSymbol,      VoidSymbol ] };
    key <AE04> { type= "FOUR_LEVEL_ALPHABETIC", [      apostrophe,              4,     VoidSymbol,      VoidSymbol ] };
    key <AE05> { type= "FOUR_LEVEL_ALPHABETIC", [       parenleft,              5,      braceleft,     bracketleft ] };
    key <AE06> { type= "FOUR_LEVEL_ALPHABETIC", [         section,              6,      paragraph,           aring ] };
    key <AE07> { type= "FOUR_LEVEL_ALPHABETIC", [          egrave,              7,  guillemotleft,  guillemotright ] };
    key <AE08> { type= "FOUR_LEVEL_ALPHABETIC", [          exclam,              8,     exclamdown,     Ucircumflex ] };
    key <AE09> { type= "FOUR_LEVEL_ALPHABETIC", [        ccedilla,              9,       Ccedilla,          Aacute ] };
    key <AE10> { type= "FOUR_LEVEL_ALPHABETIC", [          agrave,              0,         oslash,      VoidSymbol ] };
    key <AE11> { type= "FOUR_LEVEL_ALPHABETIC", [      parenright,         degree,     braceright,    bracketright ] };
    key <AE12> { type= "FOUR_LEVEL_ALPHABETIC", [           minus,     underscore,         emdash,          endash ] };

    key <AD11> { type= "FOUR_LEVEL_ALPHABETIC",	[ dead_circumflex, dead_diaeresis,    ocircumflex,     Ocircumflex ] };
    key <AD12> { type= "FOUR_LEVEL_ALPHABETIC", [          dollar,       asterisk,       EuroSign,             yen ] };

    key <AC11> { type= "FOUR_LEVEL_ALPHABETIC", [          ugrave,        percent,         Ugrave,     ucircumflex ] };
    key <BKSL> { type= "FOUR_LEVEL_ALPHABETIC", [      dead_grave,       sterling,             at,      numbersign ] };

    key <LSGT> { type= "FOUR_LEVEL_ALPHABETIC",	[            less,        greater,     VoidSymbol,      VoidSymbol ] };

    key <AB07> { type= "FOUR_LEVEL_ALPHABETIC", [           comma,       question,     VoidSymbol,    questiondown ] };
    key <AB08> { type= "FOUR_LEVEL_ALPHABETIC", [       semicolon,         period,     VoidSymbol,  periodcentered ] };
    key <AB09> { type= "FOUR_LEVEL_ALPHABETIC", [           colon,          slash,       division,       backslash ] };
    key <AB10> { type= "FOUR_LEVEL_ALPHABETIC", [           equal,           plus,     VoidSymbol,       plusminus ] };
};
EOF

Keyboard in use:

xkbcomp -xkb :0 - 2>/dev/null |grep 'name\[group'
    name[group1]="French (Macintosh)";
    name[group2]="French (alt.)";

File to modify: /usr/share/X11/xkb/symbols/fr

Search: French (Macintosh)

Add: include "mswindows-capslock" ath the end of the block.

E.g.:

[...]

// Copied from macintosh_vndr/fr
partial alphanumeric_keys
xkb_symbols "mac" {

    name[Group1]= "French (Macintosh)";

    key <TLDE> {        [          at, numbersign, periodcentered,  Ydiaeresis  ]       }; // MISSING: Ydiaeresis; eherlent : ok in Latin9

[...]

    key <KPDL> {        [  comma,KP_Decimal     ]       };

    include "level3(ralt_switch)"
    include "mswindows-capslock"
};

[...]

Update

Found another way, not tested:

setxkbmap -option caps:shiftlock

as Application autostart with the desktop environment