The complete redirect target contains a fragment, if there is any, too, not only the target page title.

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Steps to reproduce

1. (I don't know, how long this page is there with this content, but you can test the behavior with https://test.wikipedia.org/wiki/Test clicking the link TestFragment2)
2. Create a page with multiple sections
3. Create a second page which is a redirect to the first page (including a section, so add a fragment to the redirect "#Fragment")
4. Create a third page and add a link to the second page
5. Click the link in the third page

You can test it on testwiki:
https://test.wikipedia.org/w/api.php?page=TestFragment2&action=mobileview

Returns "TestFragment" as the value of "redirected" property, but should instead return "TestFragment#Fragment"