First I would like to say how great your CF7 plugin is and that other developers make plugins that work with it is a testament to that.
However I am not a programmer nor do I pretend to be one and the planned changes has me worried.
Why are you removing/abolishing the ‘on_sent_ok’ hook method (seems to work well for me)?
If you must remove the ‘on_sent_ok’ hook, why are you not making it easier on us by having something like ‘aftersubmiturl=’ in the short code?
I don’t like coding/modifying WordPress files, I like to be able to do everything from the safety of the dashboard. Modifying templates runs the risk of breaking things or creating security issues and/or having all your hard work removed on an update (if you don’t know how to create a child theme, learned that one painfully in my early years of WordPress).
I tried to use XYZ HTML Snippets to insert the ‘document.addEventListener’ script to no avail. I assume because it has to be placed somewhere special like the page header or something? A better in-depth instructions in the documentation for us code challenged people would be nice.
To sum it up please keep the ‘on_sent_ok’ hook or have the ability to set the URL redirect in the short code or at least something that does not require hacking ones WordPress install.
FYI: Why is the ‘on_sent_ok’ hook is so important to me? I have a couple main reasons – I use your CF7 plugin to collect extra information before sending them to a payment portal and/or as a multi part/page form.