I used redmine some 5 years ago.
Is it still developed actively?
Comparing osticket and redmine.
I personally tried osTicket a long ago. It worked just fine. I don't know about other two.
@tshrinivasan I have seen some people using a simple contact form upon submitting which creates an issue on gitlab. This is actually cool because you don't have to setup/maintain/switch to an additional application (if you're already using gitlab or any other forge with issues feature). You'll also get all the goodies of the issue system such as the options to assign tasks to specific members of the project, set a deadline, categorize using labels, email notifications, etc.
@tshrinivasan Well, no, the official issues form (https://docs.gitlab.com/ee/user/project/issues/managing_issues.html#accessing-the-new-issue-form) can only be used by signing in to gitlab. If you want to make it available for general public (outside gitlab), you will have to build a custom form using gitlab issues API (https://docs.gitlab.com/ee/api/issues.html#new-issue) and add it your website (assuming you already have one).
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