P2 Description
Some images are displayed incorrectly on staging. This issue occurs only on staging, i.e. arrows are shown locally and on the master branch.
Steps to reproduce the issue:
1. Open any PR, for example https://github.com/apache/beam/pull/17450
2. Follow the link to staging and open the Documentation page, or use this link: http://apache-beam-website-pull-requests.storage.googleapis.com/17450/documentation/programming-guide/index.html#schemas
3. Notice that lines or empty images are displayed instead of orange arrows (Screenshots are included)
