In order to use the tip custom element you need to import the element in the document's head:
<link href="joomla-tip.min.css" rel="stylesheet">
<script src="joomla-tip.min.js"></script>The simplified version of the custom elements
<joomla-tip label="more info" tip="This clarifies whatever needs clarifying" text="i" position="top">
</joomla-tip>
<joomla-tip label="more info" tip="This clarifies whatever needs clarifying" text="i" position="left">
</joomla-tip>
<joomla-tip label="more info" tip="This clarifies whatever needs clarifying" text="i" position="right">
</joomla-tip>
<joomla-tip label="more info" tip="This clarifies whatever needs clarifying" text="i" position="bottom">
</joomla-tip>