Jetpack Comments Conflict with Discussion Settings – "Break Comments into Pages" Disabled

### Impacted plugin

Jetpack

### Quick summary

When the "Break comments into pages" setting is disabled, Jetpack comments get stuck on "Submitting Comment" and do not auto-reload to display the posted comment. This issue only occurs on Business or higher plans and is not reproducible on simple sites.

### Steps to reproduce

1. Create a WordPress site on a Business plan or higher.
2. Ensure [hosting features are activated](https://wordpress.com/support/activate-your-business-plan/).
3. Enable the Jetpack comments module via /wp-admin/admin.php?page=jetpack_modules.
4. Disable the "Break comments into pages with X top level comments per page and the Y first page displayed by default. Comments should be displayed with the Z newer comments at the top of each page" setting in /wp-admin/options-discussion.php.
5. Open any post and submit a comment.

### A clear and concise description of what you expected to happen.

The page should reload once the comment is submitted, and the new comment should be visible.

### What actually happened

The page remains stuck on "Submitting Comment," and the comment is not displayed without a manual page reload.

### Impact

Most (> 50%)

### Available workarounds?

Yes, easy to implement

### If the above answer is "Yes...", outline the workaround.

Manually reload the page, or enable the feature "Break comments into pages with X top level comments per page and the Y first page displayed by default. Comments should be displayed with the Z newer comments at the top of each page" setting in /wp-admin/options-discussion.php to have it autoload the page.

### Platform (Simple and/or Atomic)

_No response_

### Logs or notes

- The issue is not reproducible on simple WordPress.com sites.
- Jetpack comments did not load on jurassic.ninja, so unable to confirm if the issue is reproducible in core or only isolated to Atomic. (Edit: was reproduced on jurassic.ninja here: p9F6qB-gg6-p2#comment-62815 )
- initially escalated here p9F6qB-gg6-p2

Reproduce on a Business or higher WordPress.com site with Jetpack comments enabled and “Break comments into pages” disabled, then compare the behavior with that setting enabled. Start at the Jetpack comments module and the discussion settings entry point; done means submitting a comment no longer remains stuck and the new comment appears without a manual reload.

Written by the indexing model from the issue text.