Links don't work

I am writing a wiki document in gitlab.

I use an internal editor, asciidoc markup. I mark the headings like this

== Title 2_1

== Title 2_2

===Title 3_1

I make the table of contents like this

:toc-title: Сontent

I get the table of contents in the form of links.

If you click on the link, the desired section opens in a new browser tab. Why? Is it possible to make links open in the same tab?