Reduce the Size of Icons on GNOME Dash

Edit /usr/share/gnome-shell/js/ui/dash.js

Change

...
const Dash = new Lang.Class({
    Name: 'Dash',

    _init : function() {
        this._maxHeight = -1;
        this.iconSize = 64;
        this._shownInitially = false;
...

to

...
const Dash = new Lang.Class({
    Name: 'Dash',

    _init : function() {
        this._maxHeight = -1;
        this.iconSize = 32;
        this._shownInitially = false;
...

and further down the script

...
let iconSizes = [ 16, 22, 24, 32, 48, 64 ];
...

to

...
let iconSizes = [ 16, 22, 24, 32 ];
...

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