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Examples of keywords are CommentedBy or AttachmentExtenstionAttachmentExtension. A simple JQL clause could be AttachmentExtension = png. This returns all issues that have with an attached PNG file.
JSE functions
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To use JQL Search Extensions for Jira, you should know how to write and structure a JQL query. You should understand how to use functions and keywords to build relevant and precise search results. If you need help with JQL, refer to Atassian’s Atlassian’s support documentation https://support.atlassian.com/jira-software-cloud/docs/use-advanced-search-with-jira-query-language-jql/
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