app-odoo/web_fontawesome/static/src/js/form_renderer.js

odoo.define('web_fontawesome5.FormRenderer', function (require) {
"use strict";

var FormRenderer = require('web.FormRenderer');

FormRenderer.include({

    _renderStatButton: function (node) {
        var $button = this._super.apply(this, arguments);
        if (node.attrs.brand_icon) {
            $('<div>')
                .addClass('fab fa-fw o_button_icon')
                .addClass(node.attrs.brand_icon)
                .prependTo($button);
        }
        if (node.attrs.solid_icon) {
            $('<div>')
                .addClass('fas fa-fw o_button_icon')
                .addClass(node.attrs.solid_icon)
                .prependTo($button);
        }
        if (node.attrs.regular_icon) {
            $('<div>')
                .addClass('far fa-fw o_button_icon')
                .addClass(node.attrs.regular_icon)
                .prependTo($button);
        }
        return $button;
    },
    _renderTagButton: function (node) {
        var $button = this._super.apply(this, arguments);

        if (node.attrs.brand_icon) {
            $('<div>')
                .addClass('fab fa-fw o_button_icon')
                .addClass(node.attrs.brand_icon)
                .prependTo($button);
        }
        if (node.attrs.solid_icon) {
            $('<div>')
                .addClass('fas fa-fw o_button_icon')
                .addClass(node.attrs.solid_icon)
                .prependTo($button);
        }
        if (node.attrs.regular_icon) {
            $('<div>')
                .addClass('far fa-fw o_button_icon')
                .addClass(node.attrs.regular_icon)
                .prependTo($button);
        }
        return $button;
    }
});

});