I have given read access to a project for anonymous users.
They can comment the issues but the "vote for this issue" link is disabled.
How can I allow anonymous users to vote for an issues?
You can't.
In order to record a vote, JIRA logs the user who is voting (to avoid them voting more than once). You can't log anything from an anonymous visit to usefully do that. So anonymous voting won't work, and you can't do it.
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