Unable to load all content when accessing CQ via a URL that references a nonexistent answer

Background

zverev.vasiliy35530848045926 noticed this issue on Atlassian Answers and posted a new question when he couldn't proceed – https://answers.atlassian.com/questions/35772255. It seems he's using an invalid URL because the ID of the Answer in the URL doesn't match content on the Question in question.

This is an issue because accessing Confluence Questions via an invalid link may not be a common problem, but it's easy to accidentally append or subtract a single letter from a URL when copy-pasting. This may be more widespread than we think.

When navigating to non-existant Questions, we get a message that the Question doesn't exist. When navigating to non-existant Comments on an actual Question, there is no issue. When navigating to non-existant Answers on an actual Question, we have a problem.

Steps to reproduce

Click the following URL to an answer on Atlassian Answers: https://answers.atlassian.com/questions/35762363/answers/35771303

This URL is referencing two pieces of content –

1. Question 35762363
2. Answer 35771303

Expected results

• The question (35762363) should load
• The answer (35771303) should be highlighted
• All page content should load properly

Actual results

• The question (35762363) loads
• The answer is not highlighted
• The answer is of a different ID than one would expect from the URL (35763985)
• The sidebar of 'related questions' does not render (see image)
  
• Comment and Answer editors do not load (see image)
  
• The following line is added to the browser console when clicking inside of an editor
  

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