Dev mode not working with Big Pipe

Problem/Motivation

When running Vite in Dev mode, site doesn't render Big Pipe placeholders

Steps to reproduce

1. Install Big Pipe
2. Start vite dev server
3. The placeholder spans never gets replaced

Proposed resolution

tbd

Remaining tasks

Find source of issue, seems like its related to an AJAX problem

User interface changes

n/a

API changes

n/a

Data model changes

n/a