When editing an existing comment, hot characters don't work anymore

Problem

When editing a comment, typing ~ or @ or # to mention something doesn't work anymore

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@smcgivern (can you verify if this is an regression?)

does this need backend ?

@dimitrieh I think this is a frontend regression - no requests are made to the backend to get the autocomplete data.

added frontend label

added regression label

changed milestone to %9.3

assigned to @jivanvl

Duplicate of https://gitlab.com/gitlab-org/gitlab-ce/issues/33529

Fixed in https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/12106

closed