Migration
Atlassian doesn’t support migrating Server/DC apps to Cloud apps developed with Atlassian Forge Framework. For this reason, you will need to reconfigure the add-on, after the migration. But similar issues will continue to work, because we use Jira’s own index for search.
Server/DC version has more global configuration options, but Forge (Cloud) version doesn’t have any global configuration options. Cloud version has project specific configuration options. After the migration you have to configurate project specific options. Similarity search on the “Create Issue” screen requires configuration and without configuration it will not be active as explained in administrative section.