Steps to reproduce the issue

In some web-server configuration, when JPATH_ROOT is / Joomla don't work correctly:

1. replaces slashes in web assets: HTMLHelper::convertToRelativePath()
2. when is configured without mod_rewrite work only for main page, others render as 404

Expected result

<link href="/media/vendor/fontawesome-free/css/fontawesome.min.css?5.14.0" rel="stylesheet" />

2. index.php?option=com_content&view=article&layout=edit&id=841 -> http status 200

Actual result

<link href="/mediavendorfontawesome-freecssfontawesome.min.css?5.14.0" rel="stylesheet" />

2. /index.php?option=com_content&view=article&id=841 -> http status 404
   /841-article-title -> https status 200

System information (as much as possible)

Shared web hosting, with domain connected to directory "with site separation".

(Provider: home.pl is one of the largest service providers in Poland.)

Additional comments

I had no problem with reconfiguration the server, but it took me a long time to find the problem. (And a lot of stress)

If this problem cannot be quickly dealt (HTTP 404), I suggest add warning to installator, admin and site .

if(JPATH_ROOT == '/installation' || JPATH_ROOT == '/administrator' || JPATH_ROOT == '/')