It is not possible to resize a gadget out of the box on the dashboard, the sizing is hardcoded and set when the gadget is developed so to make any changes would require creating a new custom gadget based on the code of the original.
For more details check documentarian on Creating a custom Gadget XML Specification HERE
To locate the original gadget, to start out download the jira source code, and the gadget data can be located at - <your_atlassian_jira_src_directory>/jira-project/jira-components/jira-plugins/jira-gadgets-plugin
The Jira Software Cloud Team has been busy working on a simple, secure, and reliable way to integrate your build and deployment information from Jenkins with Jira Software Cloud. This means you don’t...
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