re: Your code snippet enables loading the SQL with all Connections data via myPHPadmin?
No, let me try to explain further…
When an entry is added to Connections with addresses, phone, links, dates and such, that data is save to their respective tables. It is also saved serialized data in the main wp_connections table. This is done to keep db queries to a minimum when view entries. The data in the tables is only used when searching, custom ordering and editing.
This serialized data seems to be “corrupted” when being exported from the source db. This could be simply do to PHP version differences between the source and destination. I use “corrupted” in quotes because it seems fine and I can unserialize it without errors but on your production site, it gives errors which causes the data not to be displayed.
The code snippet I added using the Code Snippet plugin basically disables the use of the serialized cache data in the main wp_connections table. It uses the actual data from the other tables instead.
This will results in more db queries on the directory page but this is the only working solution I can come up with.
re: If this is the case, I can disable the two plugins you installed?
No, you will need to continue to use the Code Snippets plugin with that snippet in order for the viewing of the Connections entry data to be complete for the reasons I previously explained.
You can uninstall the Query Monitor plugin, but if I may, I do suggest leaving it installed, but deactivated. If you run into trouble, activate it as it can be a huge asset in trying to trace issues in WordPress and plugins.
Is this something I should report to the creators of Duplicator? Or is this something more related to Connections?
No, I think both plugins are fine … even though I am not quite sure what exactly the error you are receiving in Duplicator is and why.
I hope the better/more thoroughly explains it!