Is this XSS attack?

My dicourse version is 3.5.0,and the content security policy is on.

I send a post like:

111<a href=”https://www.baidu.com/”>aa</a>

It finally show this after I commit.

6625b26b-5d51-4cff-8826-5326d0e98977

When I click text ”aa”, it redirects to the website.
And I want to edit the post, the link disappear.

1c04269c-e43d-4952-9cac-86a4ea7bd419

Then when I tried to edit the post, the link disappeared.

What does this sentence mean?

From your description, it doesn’t look like an XSS attack.

Which composer mode do you use for editing? The rich text editor or markdown mode? There have been lots of improvements for the rich text editor in the past months. Does the same happen on try.discourse.org? If not, an update might fix this.