maiki is trying to figure out why the “notify” button is missing from the share modal on some of their Discourse sites. The button allows users to notify existing users. JammyDodger and Decorbuz explained that the feature was removed due to low usage and concerns about abuse. The removal is part of the latest Discourse update, which is why it’s still visible on some sites that haven’t updated yet. maiki expressed disappointment, as they were a power user of the feature. Decorbuz suggested showing support for a plugin version of the “Notify” feature.
Heya folks, I can’t figure out why the notify button with the pointy finger is one some of my sites and not others, and my searches are too generic so far.
I mean the notify button that will notify existing users, from the share modal:
It is missing on some instances I use, the following from a Team site:
I’d prefer to have it on, please let me know how to configure it. 
I think the notify feature has been retired:
Are the sites with it still there using Stable, or a slighter behind-latest version?
Unfortunately, it was removed entirely due to a supposed lack of usage and concerns surrounding abuse. I don’t think the team over at Discourse has any plans to bring it back to the core version.
As for why you’re still seeing it on certain Discourse instances, I assume they haven’t updated to the latest version yet.
Maybe you could show your support for a Customization > Plugin version of the “Notify” feature. 
Aw, bummer. I was one of those power users that used it. Thanks for letting me know, folks.