The issue

Copy / paste components in the pages detail subapp is not possible / not available.
The action Copy is available, but paste never appears.

There is a bunch of copy/paste actions & variations possible in the old version of the Pages app. In the new versions they are all not available.

This must be added. Probably a action config. "gap".

In the old version you can:

COPY:

• Select area: Copy component(s)
• Select a component: Copy component

PASTE:

• Select the same area (where you did copy from) as paste-target: Then Paste component(s)
• Select another area as paste-target: Then Paste component(s)

Estimate covers everything above; other UX related thoughts:

Also think about that "Copy / Paste" typically comes with notifications for both copy and paste.
They are missing on the the already existing copy action.

About the the labels of the actions (and notifications)

In the old version actions labels specifically are mentioning "component" (or component(s)).
But in the new apps (assets, pages), both actions and notifications labels have become more "generic" ... always talking about "Item" (or "Item(s)"), never mentioning Asset, Page, ...
... which is fine for me.
But avongunten probably should approve that.

BUT: Try to be precise about when using:

• Copy Item
• Copy Item(s)