Links in Via do not match links on non-Via version of the site

**Describe the bug**
The site https://stylo.ecrituresnumeriques.ca/api/v1/htmlArticle/5ffc67ae732b1700185b88da?preview=true#ref-menendez_menendez_tipologiprensa_2013 contains links that lead to a bibliography at the bottom of the page. The first link in the page (found in the text "Jesús Timoteo Álvarez sitúa esta pujanza científica a partir de mediados de la década de los setenta (Alvarez 1989, 7)" links to https://stylo.ecrituresnumeriques.ca/api/v1/htmlArticle/5ffc67ae732b1700185b88da?preview=true#ref-alvarez_introduccion_1989.

That same text on the Via version of the page links to https://consent.linksynergy.com/consent/v2/p?rmch=cs&tp=gdpr&domain=www.dallasnews.com&sought=false&in_scope=false&purposes=&vendors=&ext_id=0af6b181-bf22-46e3-a4ee-d70e6fd013ee#ref-alvarez_introduccion_1989. This problem appears to be **very** intermittent. It took me about 10 refreshes to get it to appear the first time, and maybe another 10 or so to get it to appear again (the second time the incorrect link was https://v.redd.it/qys833z06vw61/DASH_audio.mp4#ref-alvarez_introduccion_1989).

**To Reproduce**
Steps to reproduce the behavior:
1. Open via.hypothes.is
2. Enter https://stylo.ecrituresnumeriques.ca/api/v1/htmlArticle/5ffc67ae732b1700185b88da?preview=true#ref-menendez_menendez_tipologiprensa_2013
3. Check links on the page. If they look correct (i.e., they point to https://stylo.ecrituresnumeriques.ca/api...) then refresh.
4. Once links are incorrect compare them to the same link at https://stylo.ecrituresnumeriques.ca/api/v1/htmlArticle/5ffc67ae732b1700185b88da?preview=true#ref-menendez_menendez_tipologiprensa_2013.

**Expected behavior**
I would want the behavior occuring 90% of the time (i.e., links pointing to https://stylo.ecrituresnumeriques.ca/api...) to happen all of the time.

**Screenshots**
Non-Via:

In Via:

**Desktop (please complete the following information):**
- OS: Mac 10.14.6
- Chrome 90

**Additional context**
https://app.hubspot.com/contacts/6291320/ticket/403219496

Start by reproducing the issue in via.hypothes.is with the Stylo URL from the report, then compare the bibliography link targets in Via and the non-Via page. Focus on the intermittent rewriting of fragment links to unrelated external URLs. Done means the links consistently retain their Stylo API destinations.

Written by the indexing model from the issue text.