Link to annotation in context from RSS/Atom feed item

Requested [in our dev forum](https://groups.google.com/a/list.hypothes.is/d/msgid/dev/ff974bad-857e-4e77-a3e8-b7ef9bdfd2ef%40list.hypothes.is?utm_medium=email&utm_source=footer).

In RSS/Atom feed entries, the url provided leads to a view of the annotation in the Hypothesis stream. Instead (or in addition), this user would like for this link to lead to the page/document being annotated with the annotation in focus.

Example entry:

```

tag:hypothes.is,2015-09:ihEM4uLMEeeTM4Mg5CGUJw
Challenges in defining the role of intron retention in normal biology and disease
2018-09-16T00:08:23.691365+00:00
2017-12-17T01:49:37.450402+00:00

malcook








<blockquote>Finally, the fact that many IRTs are subject to NMD adds an additional layer of complexity, as the gene may be observed as expressed at a lower level due to the specific degradation of IRTs</blockquote>I do not expect there is a bioinformatics approach to account for this. The article does not suggest a bioinformatics approach for normalizing for rate of NMD, nor have I seen one elsewhere.


```

The `` leads to: https://hypothes.is/a/ihEM4uLMEeeTM4Mg5CGUJw. From this view, you can click on the link in the annotation card to be brought to https://hyp.is/ihEM4uLMEeeTM4Mg5CGUJw/www.sciencedirect.com/science/article/pii/S1084952117302938.

The user would like for the bouncer link to be part of the RSS/Atom entry.

Start by tracing the RSS/Atom feed entry that currently exposes the annotation view at hypothes.is/a/ihEM4uLMEeeTM4Mg5CGUJw, then compare it with the bouncer URL shown in the issue. The work is done when the feed entry includes a link that opens the annotated page with the annotation in focus.

Written by the indexing model from the issue text.