Why does a php file output its code to the browser?

Question

PHP

There is a site on Bitrix. put ckeditor there, then ckifinder to load images.
when you click on "Select on the server" the browse.php file is accessed, which produces this:

the file itself:

if you create it in the test.php directory with an arbitrary code, then everything will work as it should.
there are no errors, the rest of the site works fine.
help.

Answer 1

I think because it accesses through the /js/ directory, where the php interpreter does not work.

Answer 2

Is there .htaccess in this folder or one level up?
What's in it?