plone/plone.app.discussion — comment on commit 07b8ebc5df6d60f6b561771143304099beb6df4e
File:  line 0
By gaudenz:

I'm not sure if this is the right thing to do. Adding a comment does not modify the content object. I think this should rather be handled in plone.app.caching. It has the effect that objects reappear in the last modified portlet if a comment is added and that all objects with comments get their modification time reset on comment migration.