What does this mean?
The link is set to open in a new tab but the user is not being warned about this.
For example:
<a href="..." target="_blank">See guidance on links</a>
Impact on users
When links open in a new window or tab without warning it can confuse users as they may think they are still in the original tab. They may then struggle to return to the originating page as to them the browser back button is not working as expected.
How to fix
If a link is to open in a new tab, add warning text as part of the link (to ensure it is announced at point of need).
For example:
<a href="..." target="_blank">See guidance on links (opens in a new tab)</a>
References
GOV.UK guidance on opening links in a new tab