Installing a plugin with a web-item without a URL prevents the header from showing

Issue Summary

This is reproducible on Data Center: (yes)

Steps to Reproduce

1. Step 1
   Create a plugin with a web-item that's missing a URL, e.g.

    <web-item
        key="example-web-item"
        section="admin_plugins_menu/upm_section"
        weight="1"
    >
        <label key="com.example.label"/>
<!--        <link linkId="com.example.missing.url">/plugins/servlet/example</link>-->
        <tooltip key="com.example.label.tooltop"/>
    </web-item>

1. Step 2
   Install the plugin
2. Step 3
   Try to access any page in Jira

Expected Results

Pages work fine, just without the broken web-item

Actual Results

On some pages the header is not shown at all, on others (where the web-item would show, e.g. admin) will crash and not render at all

Workaround

There is no known work-around, the plugin must be uninstalled.