Issue recurring

Thank you for reporting. I wasn't even aware that such kind of problem even exists.

My understanding of the problem is that different plugins can use at least 2 different methods to override (patch) existing code (in this case: Issue#copy_from method). These methods are:
1. alias_method - like additional_tags plugin does (https://github.com/AlphaNodes/additional_tags/blob/master/lib/additional_tags/patches/issue_patch.rb)
and
2. prepend + super - like additionals and issue_recuring plugins do source:lib/issue_recurring/issue_patch.rb@2d1ffc87.

The problem is that all plugins have to patch the same code using same method consistently - otherwise problem occurs.

The question is: what kind of action do you expect from me? Whichever method of overriding issue_recurring uses, it will be incompatible with one of your other plugins. Moreover, according to this comment https://github.com/AlphaNodes/additionals/issues/71#issuecomment-591290491, prepend + super is considered preferred way of overriding code. Changing it to alias_method in issue_recurring would be a step back.

Thank you very much for this patch. I applied it and then copy issue was successful. Indeed, a tend to use as few plugins as it is possible, and this is because of avoiding compatibility problems. I use additionals because it is used by another plugin - additional_tags. Redmine lacks core tagging system and we have to use third party plugins fer that functionality.

Just to let you know, same issue is with ixti/redmine_tags and fortunately same fix works. Thanks!