During the work on ADMINCTR-408 we realize that expected behaviour after closing subapp either by closing button (in tab) or by closing with cancel/commit action could be different.

We fixed the issue (for Groovy app especially) by unifying closing behaviour with x-button closing, i.e. returning always to browser subapp. This solution won't affect e.g. Pages app (there is no closing action in page editor) but changes behaviour for content-type apps.

There are possible solutions described in this task ADMINCTR-413 but the ultimate solution would be apparently making it configurable as mention here: https://jira.magnolia-cms.com/browse/SUPPORT-15515?focusedId=326423&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-326423
(or revert the fix done in ADMINCTR-408 and refactor the Groovy app, also mentioned in linked comment)