Issue Summary

At the moment in Confluence we do not allow to install a Connect app if it has macros with keys or aliases that clash with (are equal to) macro keys or aliases of an app that is already installed for a customer. While clashes between macro keys is indeed an issue (since we use it in the content body), clashes between alias and alias or alias and macro key are questionable.

Investigation has shown, that with disabled validation:

1. Two apps that have macros with clashing aliases (not macro keys) don't cause any issues with the Confluence content or macro browser.
2. Two apps that have a macro key from one app clashing with an alias from another app don't cause issues with a content, but macro browser only displays one of the apps in this case.

Steps to Reproduce

Use the following apps to reproduce a clash between aliases:

1. https://marketplace.atlassian.com/apps/253/scroll-imagemap-for-confluence?tab=overview&hosting=cloud
2. https://marketplace.atlassian.com/apps/1219475/requirements-clarity-map?tab=overview&hosting=cloud

Clashing alias - map.

Use the following apps to reproduce a clash between an alias and a macro key:

1. https://marketplace.atlassian.com/apps/1225084/microsoft-forms-for-confluence?tab=overview&hosting=cloud (macro key: ms-forms-display, one of the aliases: forms)
2. https://marketplace.atlassian.com/apps/261/forms-for-confluence?hosting=cloud&tab=overview (macro key: forms, no aliases)

or these two:

1. https://marketplace.atlassian.com/apps/1226275/canva-embed-for-confluence?hosting=cloud&tab=overview (macro key: canva, no aliases)
2. https://marketplace.atlassian.com/apps/1225318/canva-for-confluence?hosting=cloud&tab=overview (macro key: embed-display, one of the aliases: canva)

Expected Results

Potentially we can enable validation only for macro key vs macro key clash, and disable it for alias vs alias and alias vs macro key clash. For the latter case additional investigation is required why macro browser only displays one of the apps. Potentially it could be fixed.

Actual Results

Confluence doesn't allow installing apps with clashing aliases and/or macro keys, which probably is too restrictive without a good reason.

Workaround

Disable a feature flag that enables a validation for clashing macro keys and aliases and install an app (taking into account the risk that it may cause other conflicting issues).