Issue Summary

On the upgrade documentation mentions that is possible to disable plugins prior to the upgrade, and after the upgrade is finished, upgrade to compatible plugin version.
This does not seem to work always.
There are some disabled plugins that fail to load during the upgrade, causing the upgrade to fail, some examples are "Adaptavist ScriptRunner for JIRA" "Insight", etc.

Steps to Reproduce

1. Disable plugins trough Manage Apps
2. Proceed with upgrade
3. Jira will fail to start with an error like this one:

   'com.onresolve.jira.groovy.groovyrunner' - 'Adaptavist ScriptRunner for JIRA'  failed to load.
               Cannot start plugin: com.onresolve.jira.groovy.groovyrunner
                   Unable to resolve com.onresolve.jira.groovy.groovyrunner [214](R 214.0): missing requirement [com.onresolve.jira.groovy.groovyrunner [214](R 214.0)] osgi.wiring.package; (&(osgi.wiring.package=com.atlassian.crowd.embedded.api)(version>=7.2.9)) Unresolved requirements: [[com.onresolve.jira.groovy.groovyrunner [214](R 214.0)] osgi.wiring.package; (&(osgi.wiring.package=com.atlassian.crowd.embedded.api)(version>=7.2.9))]
               It was loaded from /var/jira-home/shared/plugins/installed-plugins/plugin_6370240216098382762_groovyrunner-5.4.45.jar

And the plugin is currently disabled:

Expected Results

Upgrade to finish with success.

Actual Results

Upgrade fails because plugins are failing to start.

Workaround

1. Back up and then delete the contents of the /plugin folder in Jira. This will delete all the plugins you have.
   • a. on Server, go to <local-home-directory>/plugins.
   • b. on DC, go to <shared-home-directory>/plugins.
2. After you've upgraded, install the compatible versions of your plugins.