Cannot navigate to linter messages for large (slow) files

[kumar303]

Describe the problem and steps to reproduce it:

• Browse an add-on with a slow file (see https://github.com/mozilla/addons-code-manager/issues/947 for examples) or load a comparison for a version with slow files (see https://github.com/mozilla/addons-code-manager/issues/946 for examples).
• Navigate to a large (slow) file with linter messages. Example: https://code.addons-dev.allizom.org/en-US/browse/502868/versions/1688187/?allowSlowPages=false&path=src%2Fjs%2Feditor-popup.js
• Click one of the linter messages towards the bottom of the overview -- i.e. one that would not show up on the screen since the code has been shortened.
• Or press the z key enough times to load one of these off-screen messages

What happened?

Requesting the message does not show the message. Nothing in the UI happens. The console has an error that will look something like:

Anchor "#I18167" unexpectedly does not exist on the page

What did you expect to happen?

I'm not sure yet. Ideally, the message should be shown somehow. Alternatively, the UI could show a message saying that you need to load the entire file before you can see the requested message.

Anything else we should know?

┆Issue is synchronized with this Jira Task