You can add the tawk.to Widget to a WHMCS site by following these steps:
1. Open your cPanel
2. Go to public_html
3. Go to the folder where you installed WHMCS.
4. Open the folder “templates”
5. In folder “templates” open subfolder “portal” (looks like : /public_html/folder where you installed WHMCS/templates/portal/)
5. Find the file “footer.tpl” and click on it.
6. From the left side of your cPanel click on “Edit File” or “Edit File with Code Editor” option.
7. At the bottom of the page right ABOVE the </body> tag put:
8. Click “Save changes” (upper right corner of page)
9. Exit from cPanel.
It should look like this:
That’s it you’re done! The tawk.to widget should now appear on all pages of your WHMCS site.