Copy something to clipboard onclick

copytoclipboard.html

<lightning-input name="input5" label="Sample text" class="slds-p-bottom_medium" data-field="text" ></lightning-input>

<lightning-button variant="brand" label="Copy text" title="Share Guide" icon-name="utility:copy"
                        onclick={copyTextToClipboard} class="js-copy-btn slds-m-left_x-small"></lightning-button>

copytoclipboard.js

copyTextToClipboard() {
        let textArea = document.createElement("textarea");
        //
        // *** This styling is an extra step which is likely not required. ***
        //
        // Why is it here? To ensure:
        // 1. the element is able to have focus and selection.
        // 2. if element was to flash render it has minimal visual impact.
        // 3. less flakyness with selection and copying which **might** occur if
        //    the textarea element is not visible.
        //
        // The likelihood is the element won't even render, not even a
        // flash, so some of these are just precautions. However in
        // Internet Explorer the element is visible whilst the popup
        // box asking the user for permission for the web page to
        // copy to the clipboard.
        //

        // Place in top-left corner of screen regardless of scroll position.
        textArea.style.position = 'fixed';
        textArea.style.top = 0;
        textArea.style.left = 0;

        // Ensure it has a small width and height. Setting to 1px / 1em
        // doesn't work as this gives a negative w/h on some browsers.
        textArea.style.width = '2em';
        textArea.style.height = '2em';

        // We don't need padding, reducing the size if it does flash render.
        textArea.style.padding = 0;

        // Clean up any borders.
        textArea.style.border = 'none';
        textArea.style.outline = 'none';
        textArea.style.boxShadow = 'none';

        // Avoid flash of white box if rendered for any reason.
        textArea.style.background = 'transparent';
        textArea.value = this.template.querySelector('[data-field="text"]').value;
        document.body.appendChild(textArea);
        textArea.focus();
        textArea.select();
        try {
            let successful = document.execCommand('copy');
            let msg = successful ? 'successful' : 'unsuccessful';
            console.log('Copying text command was ' + msg);
            showMessage(this, { title: 'Copied!', message: 'Your profile link has been copied to your clipboard.', messageType: 'success', mode: 'dismissible' });
        } catch (err) {
            console.log('Oops, unable to copy');
        }

        document.body.removeChild(textArea);
    }