Show success toast after flag is sent

[NateDhaliwal]

Currently, after flagging a post, there is no indication if your flag successfully went through or not. I would like to propose a success toast appear after a flag is sent.

[Moin]

There is this:

which works as an even better confirmation for me, because I can still see that after a few hours, when I may have forgotten that I already flagged the post.