I just upgraded to ownCloud 10.x and installed the new app for Dropbox API v2 support.
I followed the instructions to set the whole thing up, but the "grant access" button does nothing and the little square on the left-hand side stays red - pretty much the exact same problem as described in the comments here.
Technically, if you check https://github.com/Hemant-Mann/files_external_dropbox/blob/master/lib/Storage/Dropbox.php you'll see the constructor expects a
configured parameter to be set to
'true', which isn't the case.
Please let me know if you need any extra info. Thanks!