wp-admin/load-styles.php returns 200 status code and empty response if required GET parameter is missing or invalid

[compilenix]

It happend to me that a nginx reverse proxy did cut off all query parameters.
This resulted in no CSS and JS for the WP backend / login.

Because the request was manipulated by a (reverse-) proxy i wasn't able to see that the request passed to wordpress was indeed "invalid", beacuse the load[] parameter is required to do something meaningful.

I want to add a small patch which checks if the load[] parameter is set and is formally valid.
In the case where the load[] parameter isn't valid there should be an appropiate indicator that there is something wrong.
With this I'm aiming to make it easier, for a developer or system administrator, to find this kind of "error".

[johnbillion]

Thanks for the patch, @compilenix, and welcome to WordPress Trac!

[pento]

Patch needs review and decision.

[desrosj]

This ticket has not received any attention during the 5.2 cycle. With beta
1 tomorrow, going to punt this to 5.3.

[desrosj]

This ticket has not received any attention during the 5.2 cycle. With beta 1 tomorrow, going to punt this to 5.3.

[SergeyBiryukov]

In 45731:

Script Loader: Send a 400 Bad Request status code in load-scripts.php and load-styles.php if the required load[] parameter is not set.

Props compilenix.
Fixes #44108.