如何删除Extra Wordpress换行符插入HTML页面和PHP文件导致解析错误

Right now, someone edited a wordpress PHP file to insert the breadcrumbs feature on the site. I thought it was in the functions.php file, but the file itself has the same problem.

The extra carrage return is inserted in all of the HTML files on the site, and most of the php files. It is also inserted in xml files and more.

What I did so far was navigate to the pages, and view page source. This confirms much more on more pages.

This is the sitemap.xml and it is preventing the website from proper SEO indexing, and many parse errors are coming out in the error log mentioning errors for include(footer.php) and include(header.php) starting on March 8th. My plan was to check the FTP for php files that were edited on or after March 8th, and start to look for weird inconsistancies, but I am not really noticing anything.

The image below is of the function.php file.

The error can be seen here as well. view-source:https://www.sunbasedata.com/sitemap_index.xml