The problem was that the default iteration limit was to high (25 posts per iteration). This simply overloaded the server. The causes usually indexing complex pages with perhaps lots of shortcodes, filters or even iframe contents. I've changed this iteration limit to 2 and finished the indexing process without the error message: https://i.imgur.com/fAeOrDh.png
Any further items will be indexed automatically upon creation.
I read you want to index navigation menu items as well. You might need an additional code for it to work, as navigation items are post types but are much harder to handle in terms of searching, so I was not able to include their support officially yet. Make sure to place this code snippet to the functions.php file in your currently active theme directory (copy from line 3):
If you need any help with this, then just add temporary FTP details to your ticket, and I will do it for you.
In addition to the IFRAME content indexing: This is probably one of the most unpredictable features of the plugin, to be honest with you. There are just so many different things one can place into an IFRAME (from simple HTML to all kinds of weird media and so on), therefore it's not an easy job to extract their contents correctly, or in some cases at all. The plugin will try it's best to recognize and extract every relevant information from there, but there is still a chance that some things might be missing.
Let me know if you need help with the code snippet above, and I hope this information helps you.Best,
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