Elementor was unable to identify the currently used page. I removed the unnecessary /index.php from the URL permalink structure, and everything is now working fine. The entire website is functioning correctly.

P.S. You still need to remove /index.php from all custom manually written URLs.

======

In WordPress, the /index.php in the URL typically appears due to the way permalinks are configured. Here are a few reasons why it might be there:

1.

Permalink Structure: If you see /index.php in your URLs, it might be because your permalink settings are not configured correctly. By default, WordPress uses a URL rewriting system that hides /index.php, but if this isn’t set up correctly, you might see it.

2.

.htaccess File: WordPress uses an .htaccess file to handle URL rewriting. If this file is missing or incorrectly configured, /index.php might show up in your URLs.

3.

Server Configuration: Your server might not support URL rewriting or might not have the necessary modules enabled. For example, on Apache servers, the mod_rewrite module must be enabled for pretty permalinks to work.

4.

Custom Permalinks: If you’re using a custom permalink structure or certain plugins, they might require /index.php to be part of the URL.

Please follow this support topic: https://wpforo.com/community/how-to-and-troubleshooting-2/sub-forum-slugs-showing-empty-page-after-migration-to-new-server/#post-117338

The support team members will answer you very soon. 

hopefully somebody can advise on below:

we have a forum installed under https://OURDOMAIN.COM/index.php /knowledgeplatform/

after migration we can see main page /knowledgeplatform/ with all menus and links to posts / sub-forums

but not any of the posts / sub-forums like below (design shows whole site header & footer but shows empty space within content section)

https://OURDOMAIN.COM/index.php/knowledgeplatform/ main-forum/

https://OURDOMAIN.COM/index.php/knowledgeplatform/ pbs/

https://OURDOMAIN.COM/index.php/knowledgeplatform/ hr/

etc.

any advise please? Thanks