Combobox or Drop Down in Salesforce lightningSnapin__PreChat Lightning Web Component

Sample Code:
HTML:

<template>
    <lightning-card title="Prechat Form">   
        <template class="slds-m-around_medium" for:each={fields} for:item="field">
            <template if:true={field.dropDown} key={field.name}>
                <div key={field.name}>Priority</div>
                <select class="slds-select" key={field.name} onchange={handlePriorityChange}>
                    <option label="Low" value="Low"></option>
                    <option label="Medium" value="Medium"></option>
                    <option label="High" value="High"></option>
                </select>
            </template>
            <template if:false={field.dropDown} key={field.name}>
                <lightning-input
                    key={field.name}
                    name={field.name}
                    label={field.label}
                    value={field.value}
                    max-length={field.maxLength}
                    required={field.required}>
                </lightning-input>
            </template>
        </template>
    </lightning-card>
    <br/>
    <lightning-button
        label="Start Chat"
        title="Start Chat"
        onclick={handleStartChat}
        class="slds-m-left_x-small"
        variant="brand">
    </lightning-button>
</template>

JavaScript:
import BasePrechat from 'lightningsnapin/basePrechat';
import { api } from 'lwc';

export default class Prechat extends BasePrechat {

    @api prechatFields;
    fields;
    namelist;
    priorityValue = 'Low';

    get priorityOptions() {

        return [
            { label: 'Low', value: 'Low' },
            { label: 'Medium', value: 'Medium' },
            { label: 'High', value: 'High' },
        ];

    }

    handlePriorityChange( event ) {
        
        console.log( 'Updated Value is', JSON.stringify( event.target.value ) );
        this.priorityValue = event.target.value;

    }

    /**
     * Set the button label and prepare the prechat fields to be shown in the form.
     */
    connectedCallback() {
        
        this.fields = this.prechatFields.map( field => {
            console.log( 'Field is ', JSON.stringify( field ) );
            let dropDown = false;
            if ( field.label == 'Priority' ) {
                dropDown = true;
            }
            const { label, name, value, required, maxLength } = field;
            return { label, value, name, required, maxLength, dropDown };
        });
        this.namelist = this.fields.map( field => field.name );

    }

    /**
     * On clicking the 'Start Chatting' button, send a chat request.
     */
    handleStartChat() {

        this.template.querySelectorAll( "lightning-input" ).forEach( input => {
            this.fields[ this.namelist.indexOf( input.name ) ].value = input.value;            
        } );
        this.fields[ this.namelist.indexOf( 'Priority' ) ].value = this.priorityValue;
        console.log( 'Updated Fields values are', JSON.stringify( this.fields ) );
        this.startChat( this.fields );

    }

}

JS-meta.xml:
<?xml version="1.0" encoding="UTF-8"?>
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata">
    <apiVersion>52.0</apiVersion>
  <isExposed>true</isExposed>
  <targets>
    <target>lightningSnapin__PreChat</target>
  </targets>
</LightningComponentBundle>


Output: