Getting 404 for Ajax Request

The steps to reproduce are an ordinary activity so there must be something else going on here. We need more reproduction and analysis to characterize the bug. This is not critical.

@cilenfen is there any other way to check root cause? If you know please share.

I would start with a newly-installed Drupal site and document the steps to cause the bug. If you can't reproduce the bug that way, then it is something to do with the setup of that site, like custom or contributed modules. But then you will have some more information.

Does Drupal show an error in its log when this occurs?

ciprian.stavovei → made their first commit to this issue’s fork.