Description:
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It would be nice if people which added comments to bug reports / feature requests could also get an email when something changes in the report.

This could be done either for everybody who has commented or for everybody who has checked a new checkbox (label could be something like "Keep me informed about changes in this report") when submitting the comment.

In my opinion this is especially useful when commenting on feature request where the original author wants to get feedback on his request. Everybody who has commented will get the answer from the requester and the opinions of other commenting people immediately after something changes in the report/request.