The purchasing page on the website indicated it was compatible with J! 3.9.0 and J1 4.0 - which is the reason we purchased the extension. We are also interested in Membership Pro, Help Desk Pro and Payment Form, IF they are also compatible with J! as noted on each products screen.
So, while checking Document Seller, please check the other three also.
Yes, please check to make sure they work with the latest Beta version of J! 4. We will purchase them (all 3) if they do. You can send us a corrected version of Document Seller if you upgrade it to work with J! 4 Beta.
Just want to update that the latest package on server is now compatible with latest Joomla 4 (I used nightly build - which is basically Joomla 4 beta 4)
You can access to My Downloads menu item, download latest package, upgrade it to your site and start setting up it
There are still one issue with drag and drop re-ordering need to be fixed (by some changes in Joomla API recently, I think there is a bug in the API but needs to spend more time with it). But that could be fixed later (in case it's a bug from Joomla, I will report it with Joomla to have it fixed)