Font awesome Icon HTML in widgets disappear on save

I think the issue is that WordPress removes empty tags from the editor. Try adding in a non-breaking space – Font Awesome should remove it so you shouldn’t see any noticeable difference:

<i class="fab fa-facebook">&nbsp;</i>

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)