When you commit the image pool, make sure you also commit the hidden object which actually contains the embedded image. I have to admit that this is not obvious, especially when the image pool is defined within the application, and you open the commit dialog via the context menu of the image pool, the hidden image object will not show up in the dialog (it only shows when you open the commit dialog from the root node of the project).
We filed CDS-46729
in our Jira database to improve this situation, so when you commit a modified image pool, the corresponding hidden objects will be automatically selected.
(We already have such a mechanism in place for the device objects.)
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